Problems

Problems

3.1 Acceleration

12.

The driver of a sports car traveling at 10.0 m/s steps down hard on the accelerator for 5.0 s and the velocity increases to 30.0 m/s. What was the average acceleration of the car during the 5.0 s time interval?

  1. –1.0 × 102 m/s2
  2. –4.0 m/s2
  3. 4.0 m/s2
  4. 1.0 × 102 m/s2
13.

A girl rolls a basketball across a basketball court. The ball slowly decelerates at a rate of −0.20 m/s2. If the initial velocity was 2.0 m/s and the ball rolled to a stop at 5.0 sec after 12:00 p.m., at what time did she start the ball rolling?

  1. 0.1 seconds before noon
  2. 0.1 seconds after noon
  3. 5 seconds before noon
  4. 5 seconds after noon

3.2 Representing Acceleration with Equations and Graphs

14.

A swan on a lake gets airborne by flapping its wings and running on top of the water. If the swan must reach a velocity of 6.00 m/s to take off and it accelerates from rest at a constant rate of 0.350 m/s2, how far will it travel before becoming airborne?

  1. −8.60 m
  2. 8.60 m
  3. −51.4 m
  4. 51.4 m
15 .
A swimmer bounces straight up from a diving board and falls feet first into a pool. She starts with a velocity of 4.00 m/s and her takeoff point is 8 m above the pool. How long are her feet in the air?
  1. 0.408 s
  2. 0.816 s
  3. 1.34 s
  4. 1.75 s
  5. 1.28 s