Question

d. An object thrown vertically upwards reaches a height of 500 m. What was its initial velocity? How long will the object take to come back to the earth? Assume g = 10 m/s2 Ans: 100 m/s and 20 s​

Answer 1

U= √2h/g

So u= 100 m/s

OBJECT TOOK A TIME OF 2u/g

SO t= 20 seconds

Answer 2

Answer:

Here at 500 m height final velocity is zero for upward motion , again for upward motion the object had to be lifted against gravity resulting 'g' negative.

To come back to the ground,at first the time for upward motion has to be calculated,then the time for falling down needs to be calculated where initial velocity is 0 , then the total time is the summation of these two