Velocity of the body on reaching the ground is same in magnitude in the following cases
a) a body projected vertically from the top of tower of height 'h' with velocity 'u'
b) a body thrown down wards with velocity 'u' from the top of tower of height 'h'
c) a body projected horizontally with a velocity 'u' from the top of tower height 'h'
d) a body dropped from the top tower of height 'h'
For the body projected vertically upwards we can write ,
V2 = (-u)2 + 2gh = u2 +2gh
For the body projected vertically downwards we can write ,
V2 = u2 +2gh
For the body projected horizontally with velocity 'u' , horizontal component of velocity just before it strikes the groud is Vh = u
And vertical component of velocity just before it strikes the ground is
Vv2 = 0 + 2gh
.: If 'v' be the speed of the projectile just before it strikes the ground is given by ,
V2 = Vh2 +Vv2 = u2 + 2gh
For the body dropped from the top of a tower of height h , its speed v just before it strikes the ground is given by
V2 = 0 +2gh
So ,option (2) is correct.
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