Answer to Question #242501 in Electrical Engineering for jopay

Question

A ball reaches the ground in 5 seconds. a) From what height in meters was it dropped? b) What would be its final velocity? c) How far has it fallen in the last second of its travel?

 

Answer 1

the speed of the object when hits the ground is the velocity at time $t^*$, where $t^*$ is the value of $t$ when $s(t) = s_G = 0$ (if your reference system is placed at $s = s_G = 0$ for the ground). Find $t^*$ and substitute back in the expression of $v$.