a stone falls from the top of a cliff into the ocean. In the air it had an average speed of 16m/s.In the water it had an average speed of 3m/s before hitting the seabed.The total distance from the top of the cliff to the seabed is 127 meters and the stone's entire fall took 12 seconds. How long did the stone fall in air and how long did it fall in the water?
Accepted Solution
A:
Let t represent the time the stone fell in the air.
distance = speed * time
t*16 + (12-t)*3 = 127 . . . . . total length of travel 13t = 91 t = 7 . . . . . time in air
The stone fell 7 seconds in the air, then 5 seconds in the water.