# What is the kinetic energy of an object with a mass of #3 kg# that has been in freefall for # 7 s#?

##### 1 Answer

Feb 26, 2017

7kJ of energy

#### Explanation:

**The acceleration on the object is g, or 9.8m/s** (assuming no air resistance) This number is a constant that applies to all objects close to the Earth.

Use the equation:

In this case, the initial velocity is zero (The object is dropped, not thrown downward) So:

Now for kinetic energy =

Which is about