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(iii)   Incandescent bulbs or bulbs have a burning filament that produces heat in addition to
                    light. This heat has a negative effect on the life of bulb and costs money.

















           Note:

           Electric heater, electric toaster, and electric iron are some examples of appliances which work on
           the property of heating effect of current.

            ELECTRIC FUSE:

            Electric fuse is a safety device which prevents the damage to an electric circuit in an electrical
            appliance due to excess flow of electric current. Electric fuse works on the principle of heating
            effect of electric current.

               Construction and Working of Electric Fuse:
              Electric fuse consists of a wire made up of an alloy of tin and lead which has a very low
               melting point.
              When current passing through the wire exceeds the maximum limit, it gets heated up. Due to
               its low melting point, it (fuse wire) melts and quickly breaks, disconnecting the circuit. This
               prevents damage to the electrical appliances.
              For low current rating, the fuse wire is thinner.
            Types of Fuse:

                i.   Cartridge fuse: It consists of a fuse wire fitted in a glass tube with its two ends
                     connected to metallic caps. It is used in television, refrigerator etc.
                ii.   Ceramic fuse: It consists of porcelain fuse socket fitted with fuse wire. It is used in
                     power supply to household.













              MCB (Miniature circuit Breaker):
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