Joe balances a stationary coin on the the tip of his finger 20 cm from the top of the table. How much work is Joe doing?

The work done by Joe is 0 J.

Explanation:

When a force is applied to an object, there will be a movement because of the applied force to a certain distance. This transfer of energy when a force is applied to an object that tends to move the object is known as work done.

The energy is transferred from one state to another and the stored energy is equal to the work done.

                                 W = F . D

where F represents the force in newton,  

          D represents the distance or displacement of an object.

Force = 0 N,   D = 20 cm = 0.20 m

                                 W = 0 0.20 = 0 J.

Hence the work done by Joe is 0 J.

heats surface water up

the inner core.

good luck: )

klicker