AP Physics 1 Question 180: Answer and Explanation
Use your browser's back button to return to your test results.
The velocity-time graph shown here represents the motion of a 500 g cart that initially moved to the right along a track. It collided with a wall at approximately time (t) = 1.0 s. Which of the following is the best estimate of the impulse experienced by the cart in this collision?
- A. 3.6 N·s
- B. 0.5 N·s
- C. 0.2 N·s
- D. 1.8 N·s
Correct Answer: D
D-Impulse is change in momentum. The initial momentum was something like (0.5 kg)(1.6 m/s) = 0.8 N·s to the right. The cart came to rest, changing its momentum by 0.8 N·s, then sped back up, again changing momentum by (0.5 kg)(2 m/s) = 1.0 N·s. Thus, the total momentum change is about 1.8 N·s.