A rock dropped from a high platform is moving at 24 m/s downward when it strikes the ground. Ignore air resistance. How fast was the rock moving when it had fallen only one-fourth of the distance to the ground?
(Points : 3)
18.0 m/s

12.0 m/s

8.0 m/s

6.0 m/s

Question

A rock dropped from a high platform is moving at 24 m/s downward when it strikes the ground. Ignore air resistance. How fast was the rock moving when it had fallen only one-fourth of the distance to the ground?
(Points : 3)
       18.0 m/s

       12.0 m/s

       8.0 m/s

       6.0 m/s

anonymous · Answer

since it is a uniformly accelerated motion, you could use one of the formulae for uniformly accelerated motion:
$$v = u + at$$
$$x = ut + \frac{ 1 }{ 2}at ^{2}$$
$$v ^{2} = u ^{2} + 2ax$$
x= displacement
u= initial velocity
v= final velocity
a= acceleration
t= time taken

anonymous · Answer

does that help or i should explain further?

anonymous · Answer

no perfect! thank you so much!!@kausarsalley!

anonymous · Answer

you are welcome!