What is the kinetic energy of an object with a mass of 3 kg that has been in freefall for 9 s?

1 Answer
Feb 26, 2016

First step is to calculate the velocity, v=u+at=0+9.8*9=88.2 ms^-1.

Second step is to use this to calculate the kinetic energy, E_k=1/2mv^2=1/2*3*88.2^2=11669 J=11.7 kJ.

Explanation:

The initial velocity, u can be assumed to be 0 ms^-1 if we are not told otherwise, and the acceleration is just the acceleration due to gravity, 9.8 ms^-2.

The kinetic energy is a function of the mass and velocity of the object.