2. At $5.00 per ton how many B.T.U.'s should be produced from 1 cent's worth of bituminous coal?
3. Try the following experiment: Place a quart of water in a teakettle and place it over the fire for 5 minutes, and note the rise in temperature and compute the number of B.T.U.'s entering the water. Place another quart of water at the same temperature in an aluminum or tin dish and heat for 5 minutes, note the rise in temperature and compute the heat used before. Which of the dishes shows the greater efficiency? How do the efficiencies of the two dishes compare? How do you account for any differences in the efficiencies found?
4. How high would 8 cu. ft. of water be lifted if all of the energy produced by burning 1 lb. of coal were used in raising it?
5. What is the mechanical equivalent of a pound of coal expressed in horse-power hours?
6. If a furnace burns 100 lbs. of coal a day and its efficiency is 50 per cent. how many B.T.U.'s are used in warming the house?
7. How many B.T.U.'s can be obtained by burning 1/2 ton of bituminous coal?
8. when a pound of water is heated from 40°F. to 212°F., how many foot-pounds of energy are absorbed by the water?
9. How many loads of coal each weighing 2 tons, could be lifted 12 ft. by the energy put into the water in problem 8?
