1. What is the name of the point where light rays from infinity coverge after passing through a lens?   Parabola   Center   Infinity   Focus   Hint Half-n-half Clue   2. What type of lens is a magnifying glass?   Plane Glass   Concave   Plano-Concave   Convex   Half-n-half Clue   3. The wire of an electric bulb is known as the   Radiator   Heating Element   Luminous Wire   Filament   Half-n-half Clue   4. The SI unit of electric current is   Mho    Farad   Ohm   Ampere   Half-n-half Clue   5. The presence of charge on a substance can be confirmed by a   Gold Leaf Electroscope   Ammeter   Thermometer   Electrodes   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   490   110   Half-n-half Clue   7. When a spring is released, its potential energy is converted to   Electrical Energy   Light Energy   Kinetic Energy   Magnetic Energy   Half-n-half Clue   FREE PREVIEW: Last 10 Questions not a part of the free preview. Get Premium Membership to view all questions.