Always use the proper significant digits and show all work for calculations.

1.As a freely falling object speeds up, what is happening to its acceleration due to gravity? Does it increase, decrease or stay the same? Explain.

2.A rock is dropped off a cliff that is 138 m tall. How long will it take to hit the ground?What is the rock's final velocity?

3.Which of the following statements about free fall and the acceleration of gravity are TRUE? List all that apply.

1. An object that is free-falling is acted upon by the force of gravity alone.
2. A falling skydiver which has reached terminal velocity is considered to be in astate offree fall.
3. A ball is thrown upwards and is rising towards its peak. As it rises upwards, it is NOT considered to be in astate offree fall.
4. An object in free fall experiences an acceleration which is independent of the mass of the object.
5. A ball is thrown upwards, rises to its peak and eventually falls back to the original height. As the ball rises, its acceleration is upwards; as it falls, its acceleration is downwards.
6. A ball is thrown upwards, rises to its peak and eventually falls back to the original height. The speed at which it is launched equals the speed at which itlands. (Assume negligible air resistance.)
7. A very massive object will free fall at the same rate of acceleration as a less massive object.
8. The value of g on Earth is approximately 9.8 m/s².
9. The symbol g stands for the force of gravity.