1. Which of the following is attracted by a magnet?   Sodium   Glass   Leather   Iron   Hint Half-n-half Clue   2. Which of the following is not a good heat insulator?   Feathers   Wood   Iron   Wool   Half-n-half Clue   3. When a spring is released, its potential energy is converted to   Magnetic Energy   Kinetic Energy   Electrical Energy   Light Energy   Half-n-half Clue   4. Metals expand on heating and contract on cooling.   True   False   5. The SI unit of electric current is   Ampere   Farad   Ohm   Mho    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)?   490   330   110   230   Half-n-half Clue   7. What type of lens is a magnifying glass?   Plane Glass   Convex   Plano-Concave   Concave   Half-n-half Clue