1. Velocity

2. Linear Motion
Motion is relative. Example : Is your book moving?
Frame of Reference- point at which a position is determined.
Position is the separation between an object and a reference point. Displacement is the change in position.
Distance- amount of separation between two objects. Distance does not include direction, it is a scalar.
Vectors- quantity that has magnitude and direction
Scalar- quantity that has just magnitude.
Displacement-the measurement of how far an object is from its original starting point. “Distance with direction.” Displacement is a vector

3. Speed and Velocity Speed and Velocity
Speed- distance traveled divided by the time interval during which motion occurred.
Speed measurements involve distance and time
Constant speed is speed that does not change
Speed is calculated by the formula:
Speed = Distance / Time
Velocity is a vector quantity of speed and must have a direction. Example 40 km/hr West

4. Speed and Velocity
Speed- measure of how fast something is moving. ( scalar ) Formula: S=d/t Velocity- change of position divided by the time interval. (vector) Formula: V = d/t Instantaneous Speed – speed at any instant Ex. Car on a highway entrance Average Velocity- total distance divided by the total time. Formula :

5. Speed and Velocity cont’d
Constant velocity – constant speed and a constant direction. Non circular constant speed. Changing Velocity- changing of speed, direction or both.

6. Velocity example problems
You attempt to catch a crazy ant. It runs at a speed of 0.8 m/s. How far did it go in 3 seconds?
A toy remote control car travels 30 cm in 12 seconds. What is its velocity (in cm/s)? In m/s? In km/hr?

7. Acceleration
Acceleration-the rate at which velocity is changing. Acceleration = change in velocity / time
An object is accelerating if its speed is changing, or its direction is changing (or both).
Examples: a car is traveling in a straight line at a constant speed. Is it accelerating?
A plane is traveling in a circle at a constant speed. Is it accelerating?