Example 10
A person steps off the end of a 3.00 m high diving board and drops to the water below. (a) How long does it take for the person to reach the water? (b) What is the person's speed on entering the water?
Example 11
You drop a rock from a bridge to the river below. When the rock has fallen 4 m, you drop a second rock. As the rocks continue their free fall, does their separation (a) increase, (b) decrease, or (c) stay the same?
Example 12
A volcano shoots out blobs of molten lava, called lava bombs, from ground level. A geologist observing the eruption uses a stopwatch to time the flight of a particular lava bomb that is projected straight upward. If the time for it to rise and fall back to the ground is 4.75 s, and its acceleration is 9.81 m/s^2 downward, what is its initial speed?
Example 13
A hot air balloon is rising straight upward with a constant speed of 6.5 m/s. When the basket of the balloon is 20.0 m above the ground a bag of sand tied to the basket comes loose. (a) How long is the bag of sand in the air before it hits the ground? (b) What is the greatest height of the bag of sand during its fall to the ground?
