Kinetic and potential energy and speed

[Hootenanny]

Good, so now we have

2*potential energy = constant

2mgh = 20mh = 100m

20h = 100

Can you now go from here?

 

[crpcrpcrp]

i'm still a little confused. so what would be the constant?

 

[crpcrpcrp]

Good, so now we have

2*potential energy = constant

2mgh = 20mh = 100m

20h = 100

Can you now go from here?

what do i do form here?

 

[crpcrpcrp]

wait...
where did u get the 100?

 

[Hootenanny]

i'm still a little confused. so what would be the constant?

The constant would be the 100m as you stated yourself.

what do i do form here?

You should solve for h, the height of the ball when the potential energy is equal to the kinetic energy

wait...
where did u get the 100?

You derived it yourself;

the potential energy=mass*gravity*height
=10*10*m
=100m

 

[wisienkas]

at starting height you know that potential energy = constant

you know the constant is potential energy + kinetic energy.

therefore the potential energy and the kinetic energy is the same if 2*potential energy=constant

you can therefore say constant/2 = potential energy or constant/2= kinetic energy

since you get the potential energy from gravity*mass*height you can simply just isolate the height since you have te energy from the constant.

its more math than physics however. hope it helps for any looking in here