Answer to Question #58107 in Physics for Christbeauty

Question

12 How large an average force is required to stop a 1400-kg car in 5.0 s if the crate's initial speed is 25 m/s?
2000 N
3500 N
9000 N
7 000N

13 A 10-g bullet of unknown speed is shot horizontally into a 2-kg block of wood suspended from the ceiling by a cord. The bullet hits the block and becomes lodged in it. After the collision, the block and the bullet swing to a height 30cm above the original position. What was the speed of the bullet? (This device is called the ballistic pendulum). Take
g=9.8ms−2
487 m/s
640 m/s
354 m/s
700 m/s