What Type of Energy Does a Blackboard Eraser Have?

[csurfus1]

Homework Statement

What type of energy does a blackboard eraser have when I hold it steady three feet about the ground?

a. potential energy
b. kinetic energy
c. electrical energy
d. spring elastic energy

Homework Equations

none.

The Attempt at a Solution

I think it is kinetic energy. But I am confused on the differences of types of energies.

 

[paisiello2]

Why do you think it has kinetic energy?

 

[BrettJimison]

Potential Energy (Gravitational potential energy)
It does not have Kinetic energy because it is not in motion in your frame. (K.E = 1/2mv^2)

It does have Potential energy since you have done work (put energy into the system) in lifting the eraser up. That energy is stored as potential energy P.E = mgh ready to be released as kinetic as soon as you let the eraser go.