Motion in One Dimension PDF

MOTION in One Dimension Scalar and Vector Quantities Distance and Displacement Speed, Velocity and Acceleration  Learning Targets At the end of the class I can….. a. differentiate quantities in terms of magnitude and direction. b. describe the motion of an object in terms of dist...

MOTION in One Dimension Scalar and Vector Quantities Distance and Displacement Speed, Velocity and Acceleration  Learning Targets At the end of the class I can….. a. differentiate quantities in terms of magnitude and direction. b. describe the motion of an object in terms of distance or displacement, speed or velocity, and acceleration. c. Solve for of distance or displacement, speed or velocity, and acceleration of a moving object.  Motion in One Dimension Kinematics is the science of describing the motion of objects using words, diagrams, numbers, graphs, and equations. Kinematics is a branch of mechanics. The goal of any study of kinematics is to develop sophisticated mental models that serve to describe (and ultimately, explain) the motion of real-world objects. Motion in One dimension implies motion along a straight line or in a single direction. Motion refers to the change in the position of an object in relation to the frame of reference or fixed point.  Motion in One Dimension Motion in One dimension implies along a straight line or in a single direction.  Scalar Quantities Scalar Quantities - are quantities that are fully described by a magnitude (or numerical value) alone. Examples: 1. Speed 2. Distance 3. Time 4. Temperature  Vector Quantities Vector Quantities - are quantities that are fully described by both a magnitude and a direction. Examples: 1. Velocity 2. Displacement 3. Acceleration  Practice Identify each quantity as SCALAR or VECTOR. 1. 5m 2. 30m/sec, East 3. 5 miles, North 4. 20 degrees Celsius 5. 256 bytes 6. 4000 Calories  Learning Targets At the end of the class I can….. ✓differentiate quantities in terms of magnitude and direction. b. describe the motion of an object in terms of distance or displacement, speed or velocity, and acceleration. c. Solve for of distance or displacement, speed or velocity, and acceleration of a moving object.  Distance and Displacement A ball was rolled 2 meters to the right and then was rolled 1 meter to the left. After which, it was rolled 2 meters to the right. Distance – 5m (2m+1m+2m = 5m) Displacement - 3m (2m - 1m +2m), to the right  Distance and Displacement Suppose a person walks 50 meters to the right, then 20 meters to the left. You can represent the displacement travelled by the person by drawing vectors on a coordinate system. Distance – 70m (50m + 20M = 70m) Displacement - 30m, to the right (70m – 20m = 30 m)  Distance and Displacement Consider a car which travels 30 kilometers south, then 15 kilometers east. After which, it travels an additional 30 kilometers north. The figure below describes the motion of the car. Distance – 75m (30km+15km+30km = 5m) Displacement - 15km, East(30km+15km-30km = 15km) to the left  Distance and Displacement Distance (S) Displacement (V) describes the total space is distance with direction. It is the covered by a moving object. shortest distance (straight path) covered by an object from the starting point to its final point. Do it yourself!! John travels 25 km North but then back-tracks to South for 10 km to pick up a friend. What is John’s total displacement?  Speed and Velocity Speed (S) Velocity (V) is a measure of the distance is a measure of the travelled per unit of time displacement travelled per unit time.  Worked example Example 1 A cyclist can travel 120 kilometers in 8 hours. What is the average speed of the cyclist? A cyclist travelling North at a rate of 120 kilometers in 8 hours. What is the average speed of the cyclist? Worked example Worked example  Worked example Example 2 How far can a bus travel in 4.5 hours if it travels along a straight highway at a speed of 40 km/hr? Worked example Worked example  Acceleration Acceleration - is defined as the change in velocity per unit of time. Acceleration  Acceleration Acceleration - is defined as the change in velocity per unit of time. 1. When an object is speeding up, the acceleration is in the same direction as the velocity. 2. When an object is slowing down, the acceleration is in the opposite direction of the velocity.  Worked example Example 1 A runner is running at a velocity of 4.5 m/s and finishes the marathon track 12 seconds later. If he reached the finish line with a velocity of 18.9 m/s, what is the acceleration of the runner during the 12 second time interval? Worked example Worked example  Let's practice! A car starts from a stoplight and is traveling with a velocity of 10 m/sec east in 20 seconds. What is the acceleration of the car? A ball rolls down a ramp for 15 seconds. If the initial velocity of the ball was 0.8 m/sec and the final velocity was 7 m/sec, what was the acceleration of the ball ? Score Description 3 The answer shows correct and complete given, solution and conclusion, using appropriate units. 2 The answer is correct but presented incomplete given, solution and conclusion, using appropriate units. 1 The answer is incorrect and incomplete given, solution and conclusion are presented without using appropriate units.