Motion Chapter 7

<p>It is the reference point for the location of the school</p> Signup and view all the answers

<p>Its position changes with time</p> Signup and view all the answers

<p>It helps in preventing harm from erratic motion</p> Signup and view all the answers

<p>Because we are also moving with the earth</p> Signup and view all the answers

<p>Motion is relative</p> Signup and view all the answers

<p>To appreciate the importance of studying motion</p> Signup and view all the answers

<p>Circular motion</p> Signup and view all the answers

<p>The earth is in motion</p> Signup and view all the answers

<p>Motion along a straight line</p> Signup and view all the answers

<p>They are all in motion</p> Signup and view all the answers

<p>Because we observe the movement of dust and leaves</p> Signup and view all the answers

<p>The roadside trees appear to be moving backwards</p> Signup and view all the answers

<p>To discuss whether the walls of the classroom are at rest or in motion</p> Signup and view all the answers

<p>It is a reference point to describe the position of the school</p> Signup and view all the answers

<p>A combination of different motions</p> Signup and view all the answers

<p>To provide a basis for comparison</p> Signup and view all the answers

<p>To express motions through simple equations and graphs</p> Signup and view all the answers

<p>It is significant in understanding various phenomena</p> Signup and view all the answers

<p>It can generate hydro-electric power</p> Signup and view all the answers

<p>To appreciate the importance of motion in daily life</p> Signup and view all the answers

<p>Motion of objects along a straight line and circular motion</p> Signup and view all the answers

<p>To learn how to control it</p> Signup and view all the answers

<p>It is necessary to describe the motion of objects relative to a fixed point</p> Signup and view all the answers

<p>The danger of erratic motion</p> Signup and view all the answers

<p>A reference point</p> Signup and view all the answers

<p>They are all in motion.</p> Signup and view all the answers

<p>Because the bus is moving relative to the trees.</p> Signup and view all the answers

<p>A reference point.</p> Signup and view all the answers

<p>It is true, but we don't directly perceive it.</p> Signup and view all the answers

<p>The motion of air.</p> Signup and view all the answers

<p>Straight line, circular, rotational, and vibrational motion.</p> Signup and view all the answers

<p>Through simple equations and graphs.</p> Signup and view all the answers

<p>It can be relative.</p> Signup and view all the answers

<p>To describe the position of an object</p> Signup and view all the answers

<p>Erratic motion</p> Signup and view all the answers

<p>To learn to control them</p> Signup and view all the answers

<p>It can be a service to human beings</p> Signup and view all the answers

<p>To think about the importance of controlling motion</p> Signup and view all the answers

<p>A reference point</p> Signup and view all the answers

<p>To ensure our safety and well-being</p> Signup and view all the answers

<p>To discuss whether the walls of the classroom are at rest or in motion</p> Signup and view all the answers

<p>Understanding motion is important in our daily lives because it helps us to be aware of and prepare for potential dangers posed by erratic and uncontrolled motion, such as in natural disasters, and also to harness the benefits of controlled motion, such as in hydro-electric power generation.</p> Signup and view all the answers

<p>It is necessary to specify a reference point when describing the position of an object because it provides a fixed point of reference with respect to which the object's position can be measured or described.</p> Signup and view all the answers

<p>Controlled motion is significant in our daily lives because it provides benefits such as the generation of hydro-electric power, which is a valuable source of energy.</p> Signup and view all the answers

<p>The purpose of describing motion is to understand and communicate the location and movement of objects in relation to a reference point.</p> Signup and view all the answers

<p>Erratic motion is uncontrolled and unpredictable, whereas controlled motion is deliberate and planned, with a specific purpose or outcome.</p> Signup and view all the answers

<p>We need to study the erratic motion of some objects because it helps us to understand and prepare for potential dangers, such as those posed by natural disasters like hurricanes and tsunamis.</p> Signup and view all the answers

<p>The reference point serves as a fixed point of reference with respect to which the motion of an object can be measured or described.</p> Signup and view all the answers

<p>The 'Think and Act' activity is significant in the context of motion because it encourages us to think critically about the importance of understanding motion in our daily lives and to take action to mitigate its risks.</p> Signup and view all the answers

<p>Objects can move in a straight line, take a circular path, rotate, vibrate, or even combine these motions.</p> Signup and view all the answers

<p>The motion of the earth is not directly perceived because it is not relative to our surroundings.</p> Signup and view all the answers

<p>A reference point is necessary to describe motion because it provides a frame of reference.</p> Signup and view all the answers

<p>If an object's position changes with time, we can infer that it is in motion.</p> Signup and view all the answers

<p>We perceive the motion of air through indirect evidence, such as the movement of dust and the movement of leaves and branches of trees.</p> Signup and view all the answers

<p>They indicate that motion is relative and can be perceived differently by different observers.</p> Signup and view all the answers

<p>Studying motion is significant because it helps us understand the natural world and is essential in many fields, such as engineering and physics.</p> Signup and view all the answers

<p>The chapter will discuss motion along a straight line and circular motion.</p> Signup and view all the answers

<p>The passenger inside the bus sees the roadside trees as moving, whereas the person standing on the roadside sees the bus and its passengers as moving.</p> Signup and view all the answers

<p>We infer the motion of air by observing the movement of dust, leaves, and branches of trees.</p> Signup and view all the answers

<p>They are all in motion.</p> Signup and view all the answers

<p>Its position changes with time.</p> Signup and view all the answers

<p>It helps us understand many natural phenomena and is essential for technological advancements.</p> Signup and view all the answers

<p>The direction of motion changes in circular motion, but remains constant in straight-line motion.</p> Signup and view all the answers

<p>They provide a fixed point of reference to measure the motion of an object.</p> Signup and view all the answers

<p>The motion of the earth is not directly perceivable because it is a very slow and uniform motion.</p> Signup and view all the answers

<p>The object is in motion.</p> Signup and view all the answers

<p>Motion can be both a risk to our safety, as seen in natural disasters like floods and hurricanes, and a service to humanity, as seen in the generation of hydro-electric power.</p> Signup and view all the answers

<p>It allows us to specify the position of the object with respect to that point.</p> Signup and view all the answers

<p>Our perceptions of motion are influenced by the reference point we choose to observe from.</p> Signup and view all the answers

<p>To learn to control them and mitigate their potential risks to human safety.</p> Signup and view all the answers

<p>It provides services to humanity, such as the generation of hydro-electric power.</p> Signup and view all the answers

<p>An object's motion can be described by its change in position with respect to a reference point over time.</p> Signup and view all the answers

<p>It is crucial for our safety and well-being, as it allows us to mitigate the risks of uncontrolled motion and harness the benefits of controlled motion.</p> Signup and view all the answers

<p>The fundamental concept is the specification of a reference point.</p> Signup and view all the answers

<p>The reference point allows us to specify the object's position in relation to it.</p> Signup and view all the answers

<p>Controlled motion is essential for generating hydro-electric power and other beneficial applications.</p> Signup and view all the answers

<p>Erratic motion is uncontrolled and unpredictable, while controlled motion is deliberate and intentional.</p> Signup and view all the answers

<p>Studying erratic motion helps us learn to control and manage it, leading to benefits for human beings.</p> Signup and view all the answers

<p>Motion is an integral part of our daily lives, influencing our perceptions, safety, and well-being.</p> Signup and view all the answers

<p>Specifying a reference point enables us to describe an object's motion in a meaningful and consistent way.</p> Signup and view all the answers

<p>Our perceptions of motion are relative to a chosen reference point.</p> Signup and view all the answers

<p>The perception of motion changes when considering different reference points because what appears to be in motion for one observer may appear to be at rest for another.</p> Signup and view all the answers

<p>An object's position changing with time indicates that it is in motion.</p> Signup and view all the answers

<p>We infer the motion of objects that we cannot directly observe through indirect evidence, such as the movement of dust and leaves.</p> Signup and view all the answers

<p>Objects can move in a straight line, take a circular path, rotate, vibrate, or exhibit a combination of these.</p> Signup and view all the answers

<p>Understanding motion is important in everyday life because it helps us make sense of the world around us.</p> Signup and view all the answers

<p>The motion of the Earth affects our daily lives through phenomena such as sunrise, sunset, and changing of seasons.</p> Signup and view all the answers

<p>Specifying a reference point is necessary to describe motion because it provides a fixed point of comparison.</p> Signup and view all the answers

<p>Our perceptions of motion are influenced by the reference point from which we observe the motion.</p> Signup and view all the answers

<p>its magnitude</p> Signup and view all the answers

<p>displacement</p> Signup and view all the answers

<p>odometer</p> Signup and view all the answers

<p>The distance covered is more than the magnitude of displacement.</p> Signup and view all the answers

<p>The distance travelled is 1850 km, but the magnitude of displacement is not specified.</p> Signup and view all the answers

<p>To compare the two and understand the difference between them.</p> Signup and view all the answers

<p>It is important to understand the difference between distance and displacement to describe the motion of an object accurately.</p> Signup and view all the answers

<p>Yes, it is possible.</p> Signup and view all the answers

<p>To determine the total distance travelled by the vehicle.</p> Signup and view all the answers

<p>Distance is the total path length covered by an object, whereas displacement is the shortest distance between the initial and final positions.</p> Signup and view all the answers

<p>The magnitude of displacement becomes zero.</p> Signup and view all the answers

<p>Only the numerical value is required, without specifying the direction of motion.</p> Signup and view all the answers

<p>To have a fixed point of comparison for the object's position.</p> Signup and view all the answers

<p>The object is in motion.</p> Signup and view all the answers

<p>It illustrates the difference between distance and displacement.</p> Signup and view all the answers

<p>The distance covered is not zero, even though the displacement is zero.</p> Signup and view all the answers

<p>Because displacement is a vector quantity.</p> Signup and view all the answers

<p>magnitude</p> Signup and view all the answers

<p>displacement</p> Signup and view all the answers

<p>odometer</p> Signup and view all the answers

<p>It remains the same</p> Signup and view all the answers

<p>Distance is the total path covered, while displacement is the shortest distance from the initial to the final position.</p> Signup and view all the answers

<p>To describe the overall motion of an object and locate its final position with reference to its initial position.</p> Signup and view all the answers

<p>Yes, under certain conditions</p> Signup and view all the answers

<p>The distance covered and the magnitude of displacement</p> Signup and view all the answers

<p>To measure the distance covered and the magnitude of displacement.</p> Signup and view all the answers

<p>Motion along a straight line</p> Signup and view all the answers

<p>OA + AC = 60 km + 35 km = 95 km</p> Signup and view all the answers

<p>35 km</p> Signup and view all the answers

<p>Because distance is a scalar quantity that only considers magnitude, while displacement is a vector quantity that considers both magnitude and direction.</p> Signup and view all the answers

<p>It allows us to describe the position of an object accurately.</p> Signup and view all the answers

<p>To specify only the numerical value, without considering direction.</p> Signup and view all the answers

<p>Distance is a scalar quantity that considers only magnitude, while displacement is a vector quantity that considers both magnitude and direction.</p> Signup and view all the answers

<p>The displacement becomes zero.</p> Signup and view all the answers

<p>magnitude</p> Signup and view all the answers

<p>The distance travelled is greater than the magnitude of displacement.</p> Signup and view all the answers

<p>To measure the distance travelled.</p> Signup and view all the answers

<p>The object is in motion.</p> Signup and view all the answers

<p>It allows us to describe the object's motion with respect to a fixed point.</p> Signup and view all the answers

<p>The distance covered is greater than the magnitude of displacement.</p> Signup and view all the answers

<p>Yes, in certain cases.</p> Signup and view all the answers

<p>To describe the overall motion of an object and to locate its final position with reference to its initial position.</p> Signup and view all the answers

<p>The overall motion and the shortest distance between the initial and final positions, respectively.</p> Signup and view all the answers

<p>Distance is the total path length covered by an object, whereas displacement is the shortest distance between the initial and final positions of an object.</p> Signup and view all the answers

<p>The displacement of an object becomes zero when it returns to its initial position.</p> Signup and view all the answers

<p>It is necessary to specify the direction of motion when describing displacement because displacement has both magnitude and direction.</p> Signup and view all the answers

<p>The reference point is essential in describing motion because it provides a fixed point of reference for measuring the position and displacement of an object.</p> Signup and view all the answers

<p>The simplest type of motion is motion along a straight line.</p> Signup and view all the answers

<p>The distance covered is the total path length covered by an object, while the magnitude of displacement is the shortest distance between the initial and final positions of an object.</p> Signup and view all the answers

<p>It is important to understand the difference between distance and displacement because they are used to describe different aspects of an object's motion.</p> Signup and view all the answers

<p>The concept of motion is closely related to our everyday experiences, as we encounter various types of motion in our daily lives.</p> Signup and view all the answers

<p>The significance of considering the initial and final positions of an object in measuring its displacement is that it allows us to determine the shortest distance between the two points, which is the magnitude of the displacement.</p> Signup and view all the answers

<p>The distance covered is greater than the magnitude of displacement, as the distance covered includes the path taken along the sides of the basketball court, while the magnitude of displacement is the shortest distance between the initial and final positions.</p> Signup and view all the answers

<p>The purpose of the odometer is to measure the distance travelled by the automobile, and it relates to the concept of distance by providing a quantitative value of the total distance covered.</p> Signup and view all the answers

<p>The significance of the difference between the final reading and the initial reading of the odometer is that it gives the total distance travelled by the car, which is 1850 km.</p> Signup and view all the answers

<p>The distance covered is greater than the magnitude of displacement, as the distance covered includes the path taken from O to A and back to B, while the magnitude of displacement is the shortest distance between the initial and final positions, which is 60 km.</p> Signup and view all the answers

<p>The significance of specifying the initial and final positions of an object in describing its motion is that it allows us to determine the direction and magnitude of the displacement, and to describe the object's motion with reference to a specific reference point.</p> Signup and view all the answers

<p>The distance covered is the total path length of the circular path, while the magnitude of displacement is zero, as the object returns to its initial position.</p> Signup and view all the answers

<p>The purpose of measuring both the distance travelled and the magnitude of displacement is to provide a comprehensive description of an object's motion, including its path and its final position with reference to its initial position.</p> Signup and view all the answers

<p>The significance of the concept of displacement is that it provides a quantitative measure of the object's motion, and it allows us to describe the object's final position with reference to its initial position.</p> Signup and view all the answers

<p>displacement</p> Signup and view all the answers

<p>distance</p> Signup and view all the answers

<p>path taken</p> Signup and view all the answers

<p>displacement</p> Signup and view all the answers

<p>to describe position</p> Signup and view all the answers

<p>95 km</p> Signup and view all the answers

<p>zero</p> Signup and view all the answers

<p>50 km</p> Signup and view all the answers

<p>The distance covered is OA + AC = 60 km + 35 km = 95 km, while the displacement is 35 km (from O to C).</p> Signup and view all the answers

<p>The initial and final positions of an object determine its displacement, which is the shortest distance between the two positions.</p> Signup and view all the answers

<p>The motion illustrates that the distance covered (OA + AC) is not equal to the magnitude of displacement (35 km), and the displacement can be zero even when the distance covered is not zero.</p> Signup and view all the answers

<p>The implication is that the object's final position coincides with its initial position, even though it has covered a certain distance.</p> Signup and view all the answers

<p>The concept is relevant in understanding the motion of objects in our daily lives, such as the distance traveled by a car and the displacement of a person walking.</p> Signup and view all the answers

<p>Specifying a reference point is necessary to describe the position and displacement of an object, as it provides a fixed point of reference.</p> Signup and view all the answers

<p>The example illustrates the simplest type of motion, where the object moves along a straight path and returns to its initial position.</p> Signup and view all the answers

<p>The implication is that the distance covered and displacement are two different physical quantities, with different values and meanings.</p> Signup and view all the answers

<p>The distance travelled is 2 × 60 km = 120 km, while the magnitude of displacement is 60 km.</p> Signup and view all the answers

<p>Yes, but only when the object moves in a straight line and doesn't change direction.</p> Signup and view all the answers

<p>To measure the total distance travelled by the vehicle.</p> Signup and view all the answers

<p>The object is in motion.</p> Signup and view all the answers

<p>It allows us to describe the position and motion of an object accurately.</p> Signup and view all the answers

<p>Distance is a scalar quantity, whereas displacement is a vector quantity.</p> Signup and view all the answers

<p>To keep track of the total distance travelled, which is essential for maintenance and navigation.</p> Signup and view all the answers

<p>It helps us navigate, travel, and understand the world around us.</p> Signup and view all the answers

<p>The distance covered is greater than the magnitude of displacement.</p> Signup and view all the answers

<p>When an object moves through a distance, but returns to its initial position, its displacement will be zero.</p> Signup and view all the answers

<p>It covers equal distances in equal intervals of time.</p> Signup and view all the answers

<p>A car moving on a crowded street or a person jogging in a park.</p> Signup and view all the answers

<p>Distance travelled is the total path covered by an object, while displacement is the shortest distance between the initial and final positions.</p> Signup and view all the answers

<p>Object A is moving at a faster rate than object B.</p> Signup and view all the answers

<p>It allows us to measure the change in position of an object.</p> Signup and view all the answers

<p>It is in non-uniform motion.</p> Signup and view all the answers

<p>To understand the motion of an object and make predictions about its future motion.</p> Signup and view all the answers

<p>The distance travelled is greater than the magnitude of displacement.</p> Signup and view all the answers

<p>Uniform motion is when an object covers equal distances in equal intervals of time. Its characteristics are that it travels at a constant speed, and the time interval in this motion is small.</p> Signup and view all the answers

<p>Non-uniform motion is when an object covers unequal distances in equal intervals of time. An example is a car moving on a crowded street or a person jogging in a park.</p> Signup and view all the answers

<p>Distance is the total length of the path traveled by an object, while displacement is the shortest distance between the initial and final positions of an object.</p> Signup and view all the answers

<p>Specifying a reference point helps to describe the motion of an object accurately and provides a frame of reference for measuring its motion.</p> Signup and view all the answers

<p>The distance traveled is the total length of the path traveled by an object, while the displacement is the shortest distance between the initial and final positions of an object.</p> Signup and view all the answers

<p>Yes, an object can have zero displacement. For example, if an object moves in a circle and returns to its initial position, its displacement is zero.</p> Signup and view all the answers

<p>Measuring the rate of motion helps to understand the characteristics of an object's motion, such as its speed and direction.</p> Signup and view all the answers

<p>Uniform motion is when an object covers equal distances in equal intervals of time, while non-uniform motion is when an object covers unequal distances in equal intervals of time.</p> Signup and view all the answers

<p>Understanding motion is essential in our daily lives as it helps us understand the movement of objects, vehicles, and people, which is crucial in various fields such as engineering, physics, and sports.</p> Signup and view all the answers

<p>Uniform motion is when an object covers equal distances in equal intervals of time, whereas non-uniform motion is when an object covers unequal distances in equal intervals of time.</p> Signup and view all the answers

<p>To determine the object's position and displacement.</p> Signup and view all the answers

<p>Displacement is the shortest distance between the initial and final positions of an object, whereas distance traveled is the total length of the path traveled by the object.</p> Signup and view all the answers

<p>The object is in motion.</p> Signup and view all the answers

<p>It measures the total distance traveled by the vehicle.</p> Signup and view all the answers

<p>An object covers unequal distances in equal intervals of time.</p> Signup and view all the answers

<p>The perception of motion changes depending on the reference point chosen.</p> Signup and view all the answers

<p>An object's position is a measure of its location, while its motion is a measure of its change in position over time.</p> Signup and view all the answers

<p>It is crucial in accurately describing and analyzing an object's motion.</p> Signup and view all the answers

<p>The object covers equal distances in equal intervals of time.</p> Signup and view all the answers

<p>When an object returns to its initial position.</p> Signup and view all the answers

<p>Non-uniform motion.</p> Signup and view all the answers

<p>The time interval should be small.</p> Signup and view all the answers

<p>Object A and Object B are moving with different rates of motion.</p> Signup and view all the answers

<p>The distance travelled is greater than the magnitude of displacement.</p> Signup and view all the answers

<p>Motion is a fundamental aspect of our daily lives, from the movement of vehicles to the motion of atoms and molecules.</p> Signup and view all the answers

<p>It allows us to measure the position and displacement of an object.</p> Signup and view all the answers

<p>To describe the motion of an object accurately.</p> Signup and view all the answers

<p>The speed of 143 km h–1 represents the rate at which an object is moving, which is the distance travelled by the object in unit time.</p> Signup and view all the answers

<p>The SI unit of speed is metre per second (m s–1 or m/s).</p> Signup and view all the answers

<p>The formula to calculate the speed of an object is v = s / t, where v is the speed, s is the distance travelled, and t is the time taken.</p> Signup and view all the answers

<p>The average speed of the object is 50 km h–1.</p> Signup and view all the answers

<p>In uniform motion, an object travels equal distances in equal intervals of time, whereas in non-uniform motion, an object travels unequal distances in equal intervals of time.</p> Signup and view all the answers

<p>The purpose of measuring the rate of motion of an object is to understand its speed and describe its motion.</p> Signup and view all the answers

<p>The signboard in Fig. 7.2(b) represents the speed of an object, which is a measure of its rate of motion.</p> Signup and view all the answers

<p>Total distance travelled and total time taken</p> Signup and view all the answers

<p>It is necessary to specify the time taken by an object to travel a certain distance to calculate its speed and understand its motion.</p> Signup and view all the answers

<p>Velocity</p> Signup and view all the answers

<p>By taking the arithmetic mean of the initial and final velocities</p> Signup and view all the answers

<p>m/s or m s-1</p> Signup and view all the answers

<p>To provide a more comprehensive understanding of the object's motion</p> Signup and view all the answers

<p>Yes, by changing its speed, direction of motion, or both</p> Signup and view all the answers

<p>Average velocity takes into account the direction of motion, while average speed does not</p> Signup and view all the answers

<p>vav = (u + v) / 2</p> Signup and view all the answers

<p>To provide a complete and accurate description of the object's motion</p> Signup and view all the answers

<p>speed</p> Signup and view all the answers

<p>metre per second (m s–1 or m/s)</p> Signup and view all the answers

<p>v = s / t</p> Signup and view all the answers

<p>50 km h–1</p> Signup and view all the answers

<p>non-uniform motion</p> Signup and view all the answers

<p>to understand the rate of motion</p> Signup and view all the answers

<p>kilometre per hour (km h–1)</p> Signup and view all the answers

<p>to understand the object's speed</p> Signup and view all the answers

<p>average velocity = (initial velocity + final velocity) / 2</p> Signup and view all the answers

<p>velocity</p> Signup and view all the answers

<p>m s–1 or m/s</p> Signup and view all the answers

<p>Average speed is total distance travelled divided by total time taken, while average velocity is calculated in the same way, but it also takes into account the direction of motion.</p> Signup and view all the answers

<p>The distance covered by the object remains the same, but the displacement becomes zero.</p> Signup and view all the answers

<p>To describe the object's velocity.</p> Signup and view all the answers

<p>Controlled motion is essential in many aspects of our daily lives, such as transportation and manufacturing.</p> Signup and view all the answers

<p>The velocity of the object changes at a non-uniform rate.</p> Signup and view all the answers

<p>Yes, an object can have zero displacement if it returns to its initial position. For example, if an object travels from A to B and then back to A, its displacement is zero.</p> Signup and view all the answers

<p>Specifying both speed and direction is necessary to describe the motion of an object comprehensively, which is represented by velocity.</p> Signup and view all the answers

<p>The average velocity of the object remains the same, equal to the initial velocity and final velocity.</p> Signup and view all the answers

<p>Uniform velocity is when the velocity of an object remains constant, while variable velocity is when the velocity of an object changes.</p> Signup and view all the answers

<p>Average velocity = (Initial velocity + Final velocity) / 2</p> Signup and view all the answers

<p>Yes, the velocity of an object can be changed by changing its direction of motion only, even if its speed remains the same.</p> Signup and view all the answers

<p>The unit of velocity is m/s or m s-1.</p> Signup and view all the answers

<p>5.33 m/s</p> Signup and view all the answers

<p>Speed is a scalar quantity that gives the magnitude of motion, while velocity is a vector quantity that gives both the magnitude and direction of motion.</p> Signup and view all the answers

<p>The average velocity is given by the arithmetic mean of the initial velocity and final velocity.</p> Signup and view all the answers

<p>Average speed</p> Signup and view all the answers

<p>Kilometre per hour (km h–1)</p> Signup and view all the answers

<p>v = s / t</p> Signup and view all the answers

<p>Speed</p> Signup and view all the answers

<p>Because the speed of an object can vary over time</p> Signup and view all the answers

<p>The speed of an object is its instantaneous rate of motion, while its average speed is the total distance travelled divided by the total time taken</p> Signup and view all the answers

<p>To calculate the speed of the object</p> Signup and view all the answers

<p>The speed of an object is directly proportional to the distance travelled</p> Signup and view all the answers

<p>The unit of speed being metre per second (m/s) is significant because it provides a standardized way to measure and compare the rates of motion of different objects.</p> Signup and view all the answers

<p>The concept of average speed accounts for the non-uniform motion of an object by dividing the total distance travelled by the total time taken, thereby providing a representative value of the object's speed over a given period of time.</p> Signup and view all the answers

<p>The speed of an object is inversely proportional to the time taken to travel a given distance, and directly proportional to the distance travelled in a given time.</p> Signup and view all the answers

<p>The signboard in Fig. 7.2(b) displays the speed of 143 km/h, which is a measure of the rate of motion of an object, in this case, a bowling ball.</p> Signup and view all the answers

<p>The speed of an object refers to its magnitude, whereas its rate of motion refers to the speed at which it covers a given distance.</p> Signup and view all the answers

<p>The concept of speed is essential in our daily lives, as it is used to measure and control the motion of vehicles, individuals, and objects, ensuring safety and efficiency.</p> Signup and view all the answers

<p>Specifying the unit of speed is essential when describing an object's motion, as it provides a standardized way to measure and compare the rates of motion of different objects.</p> Signup and view all the answers

<p>The concept of average speed enables us to describe the motion of objects that do not move at a constant speed by providing a representative value of the object's speed over a given period of time.</p> Signup and view all the answers

<p>Direction of motion</p> Signup and view all the answers

<p>By taking the arithmetic mean of the initial and final velocities</p> Signup and view all the answers

<p>It provides a comprehensive description of the object's motion, including both magnitude and direction</p> Signup and view all the answers

<p>They are the same, namely m/s or m s^-1</p> Signup and view all the answers

<p>When the object is moving in a straight line with a uniform speed</p> Signup and view all the answers

<p>To describe the motion of an object when its velocity is changing</p> Signup and view all the answers

<p>Yes</p> Signup and view all the answers

<p>Average speed is calculated as total distance divided by total time, whereas average velocity is calculated using the initial and final velocities</p> Signup and view all the answers

<p>To determine the direction of motion and the magnitude of the displacement</p> Signup and view all the answers

<p>To calculate the distance of the nearest point of lightning</p> Signup and view all the answers

<p>Speed is a scalar quantity that measures distance traveled per unit time, while velocity is a vector quantity that measures displacement per unit time.</p> Signup and view all the answers

<p>When the object moves in a straight line and does not change direction.</p> Signup and view all the answers

<p>A straight line.</p> Signup and view all the answers

<p>The total distance traveled by the car.</p> Signup and view all the answers

<p>50 km/h or 13.9 m/s.</p> Signup and view all the answers

<p>A straight line back and forth.</p> Signup and view all the answers

<p>180 m</p> Signup and view all the answers

<p>3 m s–1</p> Signup and view all the answers

<p>0 m s–1</p> Signup and view all the answers

<p>remain constant</p> Signup and view all the answers

<p>not zero</p> Signup and view all the answers

<p>constant velocity</p> Signup and view all the answers

<p>yes</p> Signup and view all the answers

<p>to understand its motion</p> Signup and view all the answers

<p>Speed is the total distance covered by an object in a given time, whereas velocity is the displacement of an object in a given time. They are equal when the motion is in a straight line.</p> Signup and view all the answers

<p>Average speed is the total distance covered by an object divided by the total time taken, which accounts for non-uniform motion by averaging out the varying speeds.</p> Signup and view all the answers

<p>The path of an object in uniform motion is a straight line.</p> Signup and view all the answers

<p>Specifying a reference point is necessary to define the position and displacement of an object, as it provides a fixed point of reference.</p> Signup and view all the answers

<p>Measuring distance covered and displacement allows us to calculate the speed and velocity of an object, respectively.</p> Signup and view all the answers

<p>The average speed is 50 km/h or 13.9 m/s.</p> Signup and view all the answers

<p>Average speed is obtained by dividing the total distance travelled by the total time taken.</p> Signup and view all the answers

<p>3 m/s</p> Signup and view all the answers

<p>0 m/s</p> Signup and view all the answers

<p>Remains constant with time</p> Signup and view all the answers

<p>Not zero</p> Signup and view all the answers

<p>To understand the object's motion</p> Signup and view all the answers

<p>Distance is the total path length covered, while displacement is the shortest distance between the initial and final positions.</p> Signup and view all the answers

<p>Velocity remains constant in uniform motion, while it varies in non-uniform motion</p> Signup and view all the answers

<p>To understand the object's motion and calculate its average velocity and speed</p> Signup and view all the answers

<p>velocity</p> Signup and view all the answers

<p>Average speed is 3 m/s, while average velocity is 0 m/s.</p> Signup and view all the answers

<p>It helps in determining the type of motion, whether uniform or non-uniform.</p> Signup and view all the answers

<p>Average velocity is equal to the total displacement divided by the total time taken.</p> Signup and view all the answers

<p>The object is at rest or has returned to its initial position.</p> Signup and view all the answers

<p>Distance covered is the total path length, while magnitude of displacement is the shortest distance between the initial and final positions.</p> Signup and view all the answers

<p>It allows us to measure the object's displacement and velocity.</p> Signup and view all the answers

<p>The velocity of the object remains constant with time.</p> Signup and view all the answers

<p>1.5 × 10^8 km</p> Signup and view all the answers

<p>3 m/s</p> Signup and view all the answers

<p>50 km/h or 13.9 m/s</p> Signup and view all the answers

<p>When the object moves in a straight line, without changing its direction.</p> Signup and view all the answers

<p>Speed is a scalar quantity, while velocity is a vector quantity, having both magnitude and direction.</p> Signup and view all the answers

<p>To calculate the distance of the nearest point of lightning.</p> Signup and view all the answers

<p>Total distance travelled by the vehicle.</p> Signup and view all the answers

<p>The average speed is the total distance covered divided by the time taken, whereas the average velocity is the displacement divided by the time taken. In a circular path, the average speed is not zero, but the average velocity is zero.</p> Signup and view all the answers

<p>The velocity of an object changes with time, having different values at different instants and points of the path.</p> Signup and view all the answers

<p>The time interval is used to divide the displacement, giving the average velocity, which is a measure of the rate of change of displacement.</p> Signup and view all the answers

<p>Yes, an object moving in a circular path can have a non-zero average speed and a zero average velocity, as it returns to its initial position.</p> Signup and view all the answers

<p>The distance covered is equal to the magnitude of displacement, as the object moves in a straight line.</p> Signup and view all the answers

<p>Velocity is a measure of the rate of change of displacement, while speed is a measure of the rate of change of distance.</p> Signup and view all the answers

<p>The direction of motion is essential in describing the velocity of an object, as it determines the direction of the velocity vector.</p> Signup and view all the answers

<p>Yes, an object's velocity can be changed by changing its direction of motion only, without changing its speed.</p> Signup and view all the answers

<p>The concept of speed of sound.</p> Signup and view all the answers

<p>When the object moves in a straight line.</p> Signup and view all the answers

<p>The total distance travelled by the car.</p> Signup and view all the answers

<p>The distance of the spaceship from the ground station is 15 × 10^8 m.</p> Signup and view all the answers

<p>The average speed of the car is 50 km/h or 13.9 m/s.</p> Signup and view all the answers

<p>Usha's average speed is 180 m/1 minute = 180 m/60 s = 3 m/s.</p> Signup and view all the answers

<p>The concept of speed of light and speed of sound.</p> Signup and view all the answers

<p>0.2 m s–2</p> Signup and view all the answers

<p>When the body's acceleration is constant over a period of time.</p> Signup and view all the answers

<p>–4 m s–2</p> Signup and view all the answers

<p>0.67 m s–2</p> Signup and view all the answers

<p>A bicycle accelerating forward.</p> Signup and view all the answers

<p>A car applying brakes to slow down.</p> Signup and view all the answers

<p>A freely falling object.</p> Signup and view all the answers

<p>A car accelerating from rest to a high speed.</p> Signup and view all the answers

<p>Acceleration is a measure of the change in the velocity of an object per unit time.</p> Signup and view all the answers

<p>The SI unit of acceleration is m s–2.</p> Signup and view all the answers

<p>Uniform acceleration is when an object's velocity increases or decreases by equal amounts in equal intervals of time.</p> Signup and view all the answers

<p>Non-uniform acceleration is when an object's velocity changes at a non-uniform rate.</p> Signup and view all the answers

<p>The formula to calculate acceleration is a = (v - u) / t.</p> Signup and view all the answers

<p>The acceleration is in the direction of velocity.</p> Signup and view all the answers

<p>The acceleration of the bicycle is 0.2 m s-2.</p> Signup and view all the answers

<p>The acceleration of the bicycle is -0.4 m s-2.</p> Signup and view all the answers

<p>Acceleration is the measure of the change in velocity of an object per unit time. It is calculated by dividing the change in velocity by the time taken.</p> Signup and view all the answers

<p>Uniform acceleration occurs when an object's velocity changes at a constant rate, whereas non-uniform acceleration occurs when the velocity changes at a non-constant rate.</p> Signup and view all the answers

<p>The unit of acceleration in the SI system is m s–2.</p> Signup and view all the answers

<p>The direction of acceleration is in the direction of velocity when an object's velocity increases.</p> Signup and view all the answers

<p>The motion of a freely falling body is an example of uniformly accelerated motion.</p> Signup and view all the answers

<p>The formula to calculate acceleration is a = (v - u) / t, where a is the acceleration, v is the final velocity, u is the initial velocity, and t is the time taken.</p> Signup and view all the answers

<p>Acceleration is significant in our daily lives as it helps us understand and control the motion of objects, which is crucial in various fields such as transportation, sports, and engineering.</p> Signup and view all the answers

<p>Acceleration is the rate of change of velocity, and it determines the change in velocity of an object over time.</p> Signup and view all the answers

<p>Uniform acceleration</p> Signup and view all the answers

<p>Negative acceleration</p> Signup and view all the answers

<p>It provides a complete description of an object's motion</p> Signup and view all the answers

<p>Braking of a car</p> Signup and view all the answers

<p>Non-uniform acceleration</p> Signup and view all the answers

<p>It helps us understand and describe the world around us</p> Signup and view all the answers

<p>Non-uniform motion</p> Signup and view all the answers

<p>To define the object's position and motion</p> Signup and view all the answers

<p>The acceleration is taken to be positive if it is in the direction of velocity and negative when it is opposite to the direction of velocity.</p> Signup and view all the answers

<p>The acceleration of the object is said to be uniform.</p> Signup and view all the answers

<p>The acceleration a is calculated as a = (v - u) / t.</p> Signup and view all the answers

<p>Uniform acceleration occurs when an object's velocity changes at a uniform rate, whereas non-uniform acceleration occurs when the velocity changes at a non-uniform rate.</p> Signup and view all the answers

<p>The motion of a freely falling body is an example of uniformly accelerated motion.</p> Signup and view all the answers

<p>The SI unit of acceleration is m s–2.</p> Signup and view all the answers

<p>Acceleration is a measure of the change in velocity of an object per unit time.</p> Signup and view all the answers

<p>The formula is a = (v - u) / t, where a is the acceleration, v is the final velocity, u is the initial velocity, and t is the time taken.</p> Signup and view all the answers

<p>Acceleration in the direction of motion increases the velocity, while acceleration against the direction of motion decreases the velocity. In everyday life, examples of acceleration in the direction of motion include a car accelerating from rest, while an example of acceleration against the direction of motion is a car braking to slow down.</p> Signup and view all the answers

<p>Uniform acceleration occurs when the rate of change of velocity is constant, while non-uniform acceleration occurs when the rate of change of velocity is not constant. Examples of uniform acceleration include a car accelerating from rest to a constant speed, while an example of non-uniform acceleration is a car accelerating on a bumpy road.</p> Signup and view all the answers

<p>The equation of motion is v = u + at, where v is the final velocity, u is the initial velocity, a is the acceleration, and t is the time. The physical significance of each term is: v represents the final velocity, u represents the initial velocity, a represents the rate of change of velocity, and t represents the time over which the acceleration acts.</p> Signup and view all the answers

<p>Acceleration is used in everyday life in many ways, such as in the design of transportation systems, the control of machines, and the prediction of the motion of objects. Examples include the acceleration of a car when speeding up or slowing down, the acceleration of a bicycle when pedaling, and the acceleration of a train when leaving a station.</p> Signup and view all the answers

<p>Acceleration plays a crucial role in the motion of a train, as it determines the rate at which the train speeds up or slows down. The physical significance of acceleration in this context is that it allows the train to accelerate from rest to a high speed, or to slow down to a stop.</p> Signup and view all the answers

<p>The acceleration of an object moving in a straight line is constant, while the acceleration of an object moving in a curved path is not constant. This is because the direction of the acceleration is changing constantly in a curved path.</p> Signup and view all the answers

<p>Acceleration is the rate of change of velocity, velocity is the rate of change of position, and time is a measure of the duration of the motion. The three quantities are related through the equation of motion, v = u + at.</p> Signup and view all the answers

<p>Acceleration is used in the design of transportation systems to predict the motion of vehicles, to design braking systems, and to optimize the performance of vehicles. Examples include the design of high-speed rail systems, the optimization of engine performance in cars, and the design of braking systems in aircraft.</p> Signup and view all the answers

<p>The acceleration values of 0.2 m s–2 and –0.4 m s–2 represent the rate of change of velocity of the bicycle in the forward and backward directions, respectively.</p> Signup and view all the answers

<p>The acceleration of the bus is negative, indicating that its velocity is decreasing, which means the bus is slowing down.</p> Signup and view all the answers

<p>The acceleration of the bicycle is positive, indicating an increase in velocity, while the acceleration of the bus is negative, indicating a decrease in velocity.</p> Signup and view all the answers

<p>The acceleration of the train is uniform, indicating that its velocity is increasing at a constant rate, which means the train is moving with a constant acceleration.</p> Signup and view all the answers

<p>The time taken by the bus to decrease its speed is 5 s, which is used to calculate the acceleration of the bus.</p> Signup and view all the answers

<p>The acceleration of the bicycle is related to the force applied to the pedals, which affects the velocity of the bicycle.</p> Signup and view all the answers

<p>The acceleration of an object represents the rate of change of its velocity, which affects its motion.</p> Signup and view all the answers

<p>Both the bus and the train exhibit acceleration, but the bus is decelerating while the train is accelerating.</p> Signup and view all the answers

<p>Acceleration</p> Signup and view all the answers

<p>2.5 m/s²</p> Signup and view all the answers

<p>Uniform acceleration is when an object's velocity increases or decreases by equal amounts in equal intervals of time, whereas non-uniform acceleration is when the velocity changes at a non-uniform rate.</p> Signup and view all the answers

<p>2 m/s²</p> Signup and view all the answers

<p>Acceleration in the direction of motion increases the object's velocity, while acceleration against the direction of motion decreases the object's velocity.</p> Signup and view all the answers

<p>m s⁻²</p> Signup and view all the answers

<p>Velocity is the rate of change of an object's position, while acceleration is the rate of change of an object's velocity.</p> Signup and view all the answers

<p>-2.5 m/s²</p> Signup and view all the answers

<p>Line graphs help to show the dependence of one physical quantity, such as distance or velocity, on another quantity, such as time.</p> Signup and view all the answers

<p>Distance-time graphs show the dependence of distance travelled by an object on time.</p> Signup and view all the answers

<p>A straight line on a distance-time graph indicates uniform speed.</p> Signup and view all the answers

<p>We can use the distance-time graph to determine the speed of an object.</p> Signup and view all the answers

<p>Graphs provide a convenient method to present basic information about motion and help to show the dependence of one physical quantity on another.</p> Signup and view all the answers

<p>We need to specify the distance travelled and the time taken to describe the motion of an object using a graph.</p> Signup and view all the answers

<p>Specifying time and distance in a distance-time graph helps to show the dependence of distance on time.</p> Signup and view all the answers