ARCHIMEDES' PRINCIPLE 69 



QUESTIONS 



1. What is Archimedes' principle? 



2. Explain the principle of the hydraulic press. 



3. If the smaller surface on a hydraulic press is two inches square, 



and the larger surface is a foot and a half square, how many 

 pounds pressure must be exerted on the smaller surface to 

 balance a weight of fifty-three pounds laid on the larger 

 surface? If the piston at the smaller surface were pushed 

 down twelve and one-quarter inches, how much would the 

 weight on the larger surface rise? 



4. What is meant by "conservation of energy"? 



5. Explain how a hydraulic elevator works. 



6. How would you construct a city water-system? 



7. What is a filter? 



