Question

a brick of mass 2 kg is dropped from a rest position at certain height . find the height if the brick strike the ground with a velocity of 19.6 m/s. what is the formula of this equetion with solution

Answer 1

                    ANSWER

                                                                                 

In these type of question, the mass of the object does not matter because we assume it is falling in vacuum.

Using the formula  $v^{2}=u^{2}-2as$,

u=0 (Since it is dropped)

a=9.8 (gravitational acceleration )

v=19.6 (given)

Let the height be s.

$19.6^{2}=2*9.8*s$

$s=19.6 m$

So, the height will be 19.6 meter.

                                                                                   

Answer 2

Answer:

in these types of questions mass does not matter

Explanation:

use Vf = $\sqrt 2gh$

vf²=2gh

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

h=$\frac{19.6^{2} }{2*9.8}$

h=$\frac{384.16}{19.6}$

h=19.6m/s