A stone is dropped from a window 5m high what is its speed

[indy92]

Ok this might be a simple problem but i have no idea how to do it;

A stone is dropped from a window 5m high what is its speed when it hits the ground.

I don't need answer i just need a formula or some guidence
Thanks

 

[rock.freak667]

What does the stone have at 5m high?(what kind of energy) when dropped...this kind of energy is converted into energy a body possesses by virtue of its motion...

Law of conservation of energy

 

[indy92]

at 5m it has gravitaitional potential energy and when its is dropped it is converted to kinetic energy
ive got the formula for GPE it is height x weight
and for kinetic energy its 1/2 x mass x speed^2

these might not be the right formulas as i don't have the mass

 

[rock.freak667]

But...weight= mass x accel. due to gravity...so if you equate the two you will get:
1/2 x mass x speed^2= Height x weight

1/2 x mass x speed^2=Height x mass x accel. due to gravity


do you see anything canceling out?

 

[indy92]

amny thanks
i appreciate your help