You fire a bullet into a 2 kg wooden block that is hanging at the bottom of a pendulum. When the bullet strikes the block, the pendulum swings upward. The bullet has a mass of 0.02 kg and strikes
the block with a speed of 300 m/s.
a. What is the speed of the block and bullet when they first start moving together? (8 points)
b. What is the maximum height reached by the pendulum? (7 points)

As part of your daily workout, you lie on your back and push with your feet against a platform attached to two stiff springs arranged side by side so that they are parallel to each other. when you push the platform, you compress the springs. you do an amount of work of 79.0 j when you compress the springs a distance of 0.230 m from their uncompressed length. (a) what magnitude of force must you apply to hold the platform in this position? (b)how much additional work must you do to move the platform a distance 0.230 m farther? (c) what maximum force must you apply to move the platform a distance 0.230 m farther?