1. If an object moves with constant acceleration, its velocity a) must be constant also b) always decrease c) increases by the same amount each second d)change by varying amount depending on its speed.
2. A man leans over the edge of a cliff and throws a rock upward at 4.9 m/s. Neglecting air resistance, two seconds later the rock's speed is a) 9.8 m/s b) 14.7 m/s c) 4.98 m/s d) zero e) none of the above
3. Twelve seconds after starting from rest, an object falling freely will have a speed of a) 10 m/s b) 50 m/s c) more than 100 m/s d)100 m/s.
4. A ball is thrown 125 meters upward and then falls the same distance back to Earth. Neglecting air resistance, its total time in the air is about 10 seconds. about 15 seconds. about 5 seconds. more than 20 seconds.