ATMOSPHERIC PRESSURE 



41 



What movement of the handle will bring water up to the spout 

 to make it run out? 



What kind of a pump is the heart? 



What kind of a pump is used for spraying trees? 



What kind of a pump is used for tire pumps for automobiles and 

 bicycles? 



When would a force pump be used in a home? 



What is the difference between a force pump and a lift pump? 



What is meant by an exhaust pump? 



Why does the gasoline in an automobile tank at the rear of 

 the car pass easily into the engine when a vacuum is used? 

 What causes the Vacuum'? 

 Why is there a small hole in the cap of the tank? 



Siphon. 



Partly fill a flask with water. Close it with a two-hole rubber stopper. 

 Through one hole insert a glass tube which has been drawn out to a jet, so 

 that the jet is inside the flask. Let the other end of the tubing dip into a 

 jar of water. Insert in the other hole another piece of glass tubing which 

 extends just through the stopper. Attach to this a piece of rubber tubing 

 the other end of which dips into water in jar B on the floor. Invert the flask 

 and fasten it to a ring stand. Fig. 32. 



As the water runs out of the flask, the air pressure will be 

 reduced inside the flask. The air on the surface of the water in 



