A ball of mass 0.5 kg is dropped from the height of 10 . . .

Question : A ball of mass 0.5 kg is dropped from the height of 10 m. The height at which the magnitude of velocity becomes equal to the magnitude of acceleration due to gravity, is ___________m [Use g=10 m/s²]

Doubt by Yana 

Solution : 

m=0.5 kg 

h=10 m

Here, 
Initial velcoity (u) = 0 m/s

Because the ball is dropped. 

Acceleration (a)
= Accerlation due to gravity (g)
= +g

v²-u²=2as
v²-u²=2ah

v²-(0)²=2gh
v²=2gh
v²/2g=h
h=v²/2g
h=g²/2g [∵v=g]
h=g/2
h=10/2

h=5

The height at which the magnitude of velocity becomes equal to the magnitude of acceleration due to gravity, is 5 m.