Brushes, battery terminals, commutator, armature, magnets
External force.
Air resistance, friction, grass rubbing on a rolling ball, etc.
If there is no external force on a moving object, it keeps going.
Forever !
The answer is 0.000824653J
You need to use the formula Mass * Velocity^2 over 2
Doubling the size of a load resistor increases the load current. Increasing the load resistance, in turn the total circuit resistance is reduced. The load current would not be half as much since when you increase the size of load resistor then load current increases.
