Understanding Dimensions of Motion

• Physics helps develop analytical and critical thinking applicable in any field.
• Physics provides a foundation for understanding the physical world and is relevant in logistics and economics.
• Studying physics provides a deeper understanding of science.
• Physics is used in economics, data analysis, and technology-related roles.
• Curriculum requirements may include physics for graduation or college admission.
• Motion is any physical movement or change in position relative to a reference point.
• Motion is described in terms of displacement, velocity, acceleration, time, and speed.

Dimensions of Motion

• Motion in one dimension occurs when a body moves in one direction, called rectilinear motion, like a car moving in a straight line.
• Motion in two dimensions occurs when a body moves along a curved path, called curvilinear motion, like a throwing paper airplane.
• Motion in three dimensions occurs when a body's position changes as it moves in space, named random motion, such as a kite in the sky.

Motion In One Dimension Parameters

• Position
• Displacement
• Velocity
• Acceleration

Distance

• Distance is the length of the path traversed by a body.
• The path may or may not be straight.

Displacement

• Displacement is the shortest distance from the initial point to the final point of the body, described as the magnitude of displacement.
• Displacement is "distance between".

Distance vs Displacement Comparison

• Distance is the length of the path traveled by a body, while displacement is the shortest distance between the initial and final positions.
• Distance is a scalar quantity; displacement is a vector quantity.
• Distance is always positive.
• Displacement can be positive or negative, depending on the reference point.
• Total distance is the algebraic sum of all distances traveled, whereas net displacement is the vector sum of individual displacements.
• Displacement is zero if the body returns to its initial position.
• Both distance and displacement are measured in meters (m).

Scalar Quantities

• Scalar quantities possess only magnitude.
• Scalar quantities are denoted by a number and a unit.
• Examples of scalar quantities include pressure (10 Newtons/m^2), length (10 meters), mass (10 kg), time (10 hours), speed (10 km/hour), work (10 Newton-meter), energy (10 Joules), and temperature (10 deg F).

Vector Quantities

• Vector quantities have both magnitude and direction.
• Examples are acceleration (10 m/s², S), force (10 Newtons, S), displacement (10 meters, NW), velocity (10 m/s, E), weight (10 Newtons, S), and momentum (10 kg.m/s, W).

Speed

• Speed is the rate of change of distance with time and is the rate of motion.
• Speed is represented by s and t.
• Average speed is the total distance an object travels divided by the time it takes to travel that distance.

More About Speed

• Instantaneous speed tells how fast a car is moving at a given instant.
• Speedometer measures instantaneous speed.
• Uniform motion means an object is moving at a constant speed in a single direction.

Velocity

• Velocity measures the speed of an object in a specific direction.
• Instantaneous velocity is the instantaneous speed at a given instant with direction corresponding to the object's direction at that time.
• Velocity is calculated as the change in displacement over elapsed time, measured in meters per second (m/s).

Speed vs Velocity

• Speed is distance traveled per unit time; velocity is displacement traveled per unit time.
• Speed is a scalar quantity; velocity is a vector quantity.
• Average speed cannot be zero; average velocity can be zero.
• Speed is always positive; velocity can also be negative.
• Speed indicates how fast a body moves; velocity indicates how fast and in what direction.
• Speed has only magnitude; velocity includes direction.

Acceleration

• Acceleration refers to the change in velocity of a moving object per unit of time, represented by 'a'.
• Change in velocity can be achieved by: Increasing speed while traveling in a straight line, decreasing speed while traveling in a straight line, and changing direction even while traveling at a constant speed.

Retardation

• If the velocity decreases with time, the acceleration is negative.
• Negative acceleration is called retardation or deceleration.

Types of Motion

• Up and down motion, ex. seesaw
• Straight-line motion
• Round and round motion, ex. merry go round.
• Zigzag motion
• Back and forth motion, ex. swing.

More Motion Types

• Translational motion
• Rotational motion
• Oscillatory motion

Motion Type Details

• Random Motion: The irregular motion of small particles suspended in a liquid or a gas.
• Rotational Motion: A circular movement of an object around a center point, like a wheel.
• Translational Motion: The motion in which all points of a body move uniformly in a same line or direction ex. car or train.
• Oscillating Motion: Motion backwards and forwards in a circular arc

Uniform Motion

• An object covers equal distances in equal intervals of time.

Non-Uniform Motion

• An object covers unequal distances in equal intervals of time.

Equation of Motion

• When an object moves along a straight line with uniform acceleration: it is possible to relate to its velocity, acceleration during motion, and the distance covered by it in a certain time interval by a set of equations.

Equation for Velocity (Time Related)

• Acceleration, a = change in velocity / time.
• Where change in velocity is v2 - v1,
• Thus, a = (v2 - v1) / t
• at = v2 - v1

Equation for Position (Time)

• Distance, x = AVERAGE VELOCITY * TIME