Question

1) A crash test dummy with a mass of 65-kg is in a moving car going at 20 m/s, until it crashes into a wall. If the applied force was measured at 1,750 N, how long (in seconds) did the collision last?

2) Consider two hockey pucks on frictionless ice: Puck A with a mass 1.10 kg, and Puck B with a mass of 0.60 kg.

Puck A is initially moving to the right at 1.75 m/s towards puck B, which is initially stationary. The pucks collide head on.

After the collision, puck B moves to the right with a speed of 1.70 m/s.

What is puck A’s velocity (in m/s) after the collision? Round to the nearest hundredth (0.01) and use sign notation to denote if it's moving to the right (+) or to the left (-).

3) A 145-gram baseball flies towards a catcher at a speed of 45 m/s. The batter hits the baseball with an average force of 800 N and the collision time lasts 0.02 seconds, what will the baseball's speed (in m/s) be after being batted? Round to the nearest hundredth (0.01).

Answer 1