College Physics with MasteringPhysics 7th Edition by Jerry Wilson,Anthony Buffa,Bo Lou

Exercise 21

A car initially traveling to the right at a steady speed of 25 m/s for 5.0 s applies its brakes and slows at a constant rate of 5.0 m/s 2 for 3.0 s. It then continues traveling to the right at a steady but slower speed with no additional braking for another 6.0 s. (a) To help with the calculations, make a sketch of the car's velocity versus time, being sure to show all three time intervals.(b) What is its velocity after the 3.0 s of braking (c) What was its displacement during the total 14.0 s of its motion (d) What was its average speed for the 14.0 s