Unformatted text preview: The Dodge Caravan has the higher final speed even though it had the smaller initial speed. Exercise 16. We obtain this result by using our definition of the average acceleration. The important thing is the change in velocity, not the individual velocities. 120 km/h 0 km/h km/h 6 20 s s v a t ∆-= = = ∆ Problem 20. (a) The definition for the average acceleration is the change in velocity divided by the time taken. Therefore, 69 mph 0 mph mph 3.56 19.4 s s v a t ∆-= = = ∆ Because the car is speeding up, the direction of the acceleration is the same as that of the final velocity. (b) The definition of the average speed is the distance traveled divided by the time taken. Therefore, 0.25 miles 0.0129 miles/s 19.4 s d s t = = = Because this number is hard to interpret, let’s convert it to mph. miles 3600 s 0.0129 46.4 mph s 1 h = ÷...
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- Fall '02
- Acceleration, Velocity, Dodge Caravan