Question

An object thrown vertically upwards reaches a height of 500 m. What was its initial velocity? How long will the object take to comeback to the earth? Assume g = 10 m/s2

Answer 1

Answer:

Let the initial velocity = u

final velocity = v

v= 0 m/s

s = 500 m

2gs = v

2

−u

2

2 (-10) 500 = u

2

u = 100 m/s

v = u + at

0 = 100 - 10 t

t = 10 s

total time taken = 20 sec

Answer 2

Answer:

Time required by an object to go up is same as time required to come down. Hence total time to come back to earth is 20 seconds.