Question

An object has a kinetic energy of 810 J after falling a certain distance. If the mass of the object is 20kg, what is the speed of the object at this time?
I need the equation and answer please!

Answer 1

Don't let the "falling" confuse you. A moving object's kinetic energy is

K.E. = 1/2 (mass) (speed^2)

no matter what direction it's moving, or why.

In this problem, you know the KE and the mass, so

810 J = 1/2 (20 kg) (speed^2).

I think you can probably find the speed now.