Conservation of Energy 



Application 16. Suppose 

 you wanted to lift a heavy 

 frying pan off the stove. 

 You have a cloth to keep 

 it from burning your hand. 

 Would it be easier to lift it 

 by the end of the handle or 

 by the part of the handle 

 nearest the pan ? 



Application 17. A boy 

 was going to wheel his little 

 sister in a wheelbarrow. 

 She wanted to sit in the 

 middle of the wheelbarrow ; 

 her brother thought she 

 should sit as near the han- 

 dles as possible so that she 

 would be nearer his hands. 

 Another boy thought she 

 should sit as near the wheel 

 as possible. Who was right ? 



Application 18. James 

 McDougal lived in a hilly 

 place. He was going to buy a bicycle. " I want one that will 

 take the hills easily," he said. The dealer showed him two 

 bicycles. On one the back wheel went around three times 

 while the pedals went around once; on the other the back 

 wheel went around four and a half times while the pedals 

 went around once. Which bicycle should James have 

 chosen? If he had wanted the bicycle for racing, which 

 should he have chosen ? 



Application 19. A wagon stuck in the mud. The driver 

 got out and tried to help the horse by grasping the spokes 

 and turning the wheel. Should he have grasped the spokes 

 near the hub, near the rim, or in the middle ? 



FIG. 33. With this arrangement the pail 

 travels more slowly than the hand. Will 

 it seem heavier or lighter than with the 

 arrangement shown in Figure 32? 



