Question

A body falls freely from a height h its average velocity when it reaches earth is

Answer 1

Answer:

h=ut +1/2at², As the body is dropped ,hence u=initial velocity=0 . The acceleration is equal to g. Hence , average velocity is √gh/√2.

Answer 2

Given,

A body falls freely from a height h

To Find,

Its average velocity when it reaches the earth is =?

Solution,

We can solve the question as follows:

It is given that a body falls freely from a height h. We have to find its average velocity when it reaches the earth.

The initial velocity of the body will be zero. The acceleration of the body will be equal to the acceleration due to gravity since it is free-falling.

$initial\: velocity = u$

$acceleration = g$

$Height = h$

Now, the second equation of motion states that:

$s = ut + \frac{1}{2} gt^{2}$

Using the above equation, we will find the time taken by the body.

$h = 0*t + \frac{1}{2} gt^{2}$

$\frac{2h}{g} = t^{2}$

$t = \sqrt{\frac{2h}{g} }$

Now, the average velocity will be equal to the height divided by the time taken.

Therefore,

$Average\: velocity = \frac{h}{\sqrt{\frac{2h}{g} } }$

                           $= \sqrt{\frac{gh^{2} }{2h} }$

                           $= \sqrt{\frac{gh }{2} }$

Hence, the average velocity will be equal to sqrt(gh/2).