TranSfer of Enegry
Skiing shows the basic ways of how work and energy are related. What exactly does happen when you strap your skis in and head down the mountain?
Well first off when you're at rest on top of the hill all the energy is in the potential form, because you have taken an elevated position. As the skier heads down the slope all the potential energy is being lost, thus turning into kinetic energy and the skier gains speed down the hill. We can look at this as a closed system and conservation of energy is conserved.
Kf + Uf = Ki + Ui
What if the skier moves at a constant velocity? If the skier is moving at a constant speed all the potential energy changes into thermal energy. Since speed is not being gained all the potential energy is transferred to heating the snow, which is pretty cool.
Friction is a big factor in how it takes away the total mechanical energy of the skier. If the skier hits a rough patch of snow friction acts in the opposite of the direction (Force*displacement*cos(angle))
This increases the amount of work done to the skier which therefore slows the skier down, decreasing the total mechanical energy.
