Question

a metal bal is held at rest H=65.0 cm above the floor. The ball is released with no initial velocity. How much time does it take to hit the floor?

Answer 1

Metal ball will take 0.364 seconds to reach floor.

Explanation:

Initial height from ground = 65 cm = 0.65 meter

We have equation of motion ,
`s= ut+(1)/(2) at^2`, s is the displacement, u is the initial velocity, a is the acceleration and t is the time.

In this the velocity of body in vertical direction = 0 m/s, acceleration =acceleration due to gravity = 9.8
`m/s^2`, we need to calculate time when s = 0.65 meter.

Substituting

`0.65=0*t+(1)/(2) *9.8*t^2\\ \\ t = 0.364 seconds`

So it will take 0.364 seconds to reach floor.