Assignment:
1. A space probe may be carried by a rocket into outer space. What keeps the probe moving after the rocket no longer pushes it?
2. The smokestack of a stationary toy train consists of a vertical spring gun that shoots a steel ball a meter or so straight into the air-so straight that the ball always falls back into the smokestack. Suppose the train moves at constant speed along the straight track. Do you think the ball will still return to the smokestack if shot from the moving train?
3. Suppose that the three balls shown in Exercise 19 start simultaneously from the tops of the hills. Which one reaches the bottom first? Explain.
4. Which is greater, an acceleration from 25 km/h to 30 km/h or one from 96 km/h to 100 km/h if both occur during the same time?
5. Gravity on the surface of the moon is only 1/6 as strong as gravity on earth. What is the weight of 10-kg object on the Moon and on Earth? What is the mass on each?
6. A grocery bag can withstand 300N of force before it rips apart. How many kilograms of apples can it safely hold?
7. If you exert a horizontal of 200N to slide a crate across a factory floor at constant velocity. How much friction is exerted by the floor on the crate? Is the force of friction equal and opposite directed on your 200-N push? If the force of friction isn't the reaction force to your push, what is?
8. If a Mack truck and Honda Civic have a head -on-collision, upon which vehicle is the impact force greater? Which vehicle experiences the greater deceleration? Explain your answers.