1. PHYSICS LECTURE 5: VELOCITY Applied Physics and Chemistry

2. Velocity Definition:  Rate of change of position  Velocity = displacement/time  Slope of the line on a position/time graph  Note: This is a VECTOR quantity! Calculation:  V = d/t

3. Average versus Instantaneous Average velocity:  Average over entire movement  Average velocity = total displacement/total time  This is the slope of a position/time graph Instantaneous velocity:  Velocity at one point in time during travel  This is what you see on the speedometer

4. Examples A high speed train takes 2.00 hours to travel from Paris 454 km due south to Lyons. What is the average velocity of the train? Nora jogs several times a week and always keeps track of how much time she runs. One day she forgets to take her stopwatch with her. As she passes a particular bank, she remembers it is 4.3 km from her house. She knows from previous training that she has a constant pace of 4.0 m/s. How long has Nora been jogging when she reaches the bank?

5. More Examples! Light from the sun reaches Earth in an average of 8.3 minutes. The speed of light in a vacuum is 3.00 x 10 8 m/s. How far is Earth from Sol? You and a friend each drive to a location 50 km away. You travel at 90 km/h; your friend travels at 95 km/h. How long will your friend have to wait for you to arrive?