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Figure 6 Kinetic energy is transferredfrom domino to domino bytapping the first one in line.Figure 7 Potential and kineticenergy change as the skier movesup and down the slope.Explain how the skier’s energychanges as she moves from the topof the hill to the bottom.Transferring Kinetic Energy Kinetic energy can be transferredfrom one object to another when they collide. Thinkabout the transfer of energy during bowling. Even if the bowlingball does not touch all of the pins, it still can knock them alldown with one roll. The bowling ball transfers kinetic energy toa few pins. These pins move and bump into other pins, transferringthe kinetic energy to the remaining pins and knockingthem down.A transfer of kinetic energy also takes place when dominoesfall. You need to give only the first domino in the row a bit ofkinetic energy by lightly tapping it to make it fall against thenext domino. As the first domino falls into the next one, itskinetic energy is transferred to the second domino, as shown inFigure 6. This transfer of kinetic energy continues from dominoto domino until the last one falls and hits the table. Then, thelast domino’s kinetic energy is transferred to the table.Potential EnergySuppose the ski lift in Figure 7 takes a skier to the top of ahill. The skier has no kinetic energy when she is standing at thetop of the hill. But as she skis down and moves faster, her kineticenergy increases. Where does this kinetic energy come from?Gravity pulls the skier down the hill. If the skier were standingat the bottom of the hill, gravity would not start her moving, asit does when she is at the top of the hill. When the skier’s positionis at the top of the hill, she has a form of energy calledpotential energy. Potential energy is energy that is storedbecause of an object’s position. By using the ski lift to take herto the top of the hill, the skier increased her potential energy bychanging her position.Her potential energyis largest at the top ofthe hill.The skier's potential energyincreases as the ski lift carriesher up the hill.As she skis down hill, potentialenergy transforms into kineticenergy.Here her kinetic energy isgreatest and her potentialenergy is smallest.166Paul Avis/Liaison Agency/Getty Images