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. Study the electric circuits given below and fill in the blanks., , , , (a) will not, the switch is off, , (b) will not, there is only one wite cor, s only o ‘onnected to the positive terminal which results in, incomplete circuit Mee, , (c)_ will not, the switch is not connected which makes the circuit incomplete, (a) will not, the wood is an insulator, , (e) Fi (ii), . Write True ot False, (a) Tue (b) False (c) False (d) False, (e) Tre () Tre (g) Tue (h) True, (i) False @) False (k) True, | Give one word for each of the following., (a) Battery (b) Filament, (©) Blectric cell (d) Electric switch, . Very short answer type questions,, (a) The parts of a dry cell are- a metal cap which is the positive terminal and a metal, disc which is the negative terminal., , ) Tungsten, c) A dosed circuit, Copper, Short answer type questions., An electric switch is a device that opens or closes an electric circuit., 5) An electric bulb whose filament is broken is said to be fused,, c) Materials that do not allow electric current to pass through them are called insulators., For example: wood, glass, plastic, etc., d) If the two terminals of an electric cell are connected directly with a wire, the cell will, get destroyed or dead very soon, . Long answer type questions., (a) An electric bulb is used to light up houses. It is also used in torches and headlights, in cars. An electric bulb consists of an outer glass case that is fixed to a metallic disc, A coiled that is called filament, which is made of tungsten metal, is fixed inside the, glass case. The filament is connected to two thick wires. One wire that touches the, metal casing is the negative terminal, while the other wire which touches the metal tip, is the positive terminal, The two terminals of the bulb do not touch each other. The, electric bulb is filled with inert gases like argon, neon, etc, when the two terminals of, the bulb are joined to an electric cell, electric current flows through the circuit, heating, the filament and making it glow., (b) Conductors: Materials that allow electric current to pass through them are called, conductors, For example: copper, graphite, etc, Insulators: Materials that do not allow electric current to pass through them are called, insulators. For example: wood, glass, plastic, etc., Plastic and wood are insulators, They do not allow electric current to pass through, them. For this reason, they are used to cover the handles of the electrical appliances., In the case of a screwdriver, the plastic-covered handle of screwdriver protects the, person testing the electric fault in a circuit from getting an electric shock., , New Learnwell TM-Science-VI ES, , a, , , , , , (c)