concave - converging mirror, convex - diverging mirror, magnifying glass - convex lens, fuse - high resistance ,low melting point, element - high resistance ,high melting point, connection wire - low resistance, high melting point, electromagnet - magnetism can be controlled, iron strip - gets attracted to electromagnet in an electric bell, hammer - strikes the gong to produce sound in an electric bell, concave mirror - dentist use it to check the teeth ,

class 7

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