A racquetball strikes a wall with a speed of 25 m/s and rebounds in the opposite direction with a speed of 20 m/s. The collision takes 15 ms. What is the average acceleration of the ball during the collision with the wall? 200 m/s 2800 m/s 2 2 -333 m/s O m/s 2 -3000 m/s

Classes are canceled due to snow, so you take advantage of the extra time to conduct some physics experiments. You fasten a large toy rocket to the back of a sled and take the modified sled to a large, flat, snowy field. You ignite the rocket and observe that the sled accelerates from rest in the forward direction at a rate of 13.5 m/s2 for a time period of 3.30 s. After this time period, the rocket engine abruptly shuts off, and the sled subsequently undergoes a constant backward acceleration due to friction of 6.15 m/s2. After the rocket turns off, how much time does it take for the sled to come to a stop? time: ? By the time the sled finally comes to a rest, how far has it traveled from its starting point? distance traveled: ?

The trap-jaw ant, found throughout tropical South America, catches its prey by very rapidly closing its mandibles around  its victim. Shown is the speed of one of its mandible jaws versus time in microseconds. a. What is the maximum acceleration of the ant’s mandible? b. The mass of a trap-jaw ant’s mandible has been estimated to be about 1.3 x 10-7 kg. Estimate the maximum force exerted by one mandible.

P09