1. A bicycle dynamo generates Direct Current.   True   False   2. A freely suspended magnet always aligns itself along the   North South Axis   West South Axis   East West Axis   East South Axis   Hint Half-n-half Clue   3. The high pitched cries of a bat are above human hearing.   True   False   4. Metals expand on heating and contract on cooling.   True   False   5. How much heat is required to raise the temperature of 1g of water by 1 oC.   1 Calorie   100 Joules   1 Joule   100 Calories   Half-n-half Clue   6. What is the speed of sound in air in meters per second (at a pressure of one atmosphere and temperature of 25oC)?   230   330   110   490   Half-n-half Clue   7. What is the name of the point where light rays from infinity coverge after passing through a lens?   Parabola   Infinity   Focus   Center   Half-n-half Clue