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www.GOALias.blogspot.composition. Does the bulb glow? Touchthe bulb. Now move the electric switchto the ‘ON’ position and let the bulb glowfor a minute or so. Again touch the bulb.Do you feel any difference? After movingthe switch back to the ‘OFF’ position,touch the bulb again.Activity 14.3Make a circuit as shown in Fig.14.10.Take about 10 cm long piece of nichromewire and tie it between the nails. (Youcan get nichrome wire from an electricrepair shop or you can use a piece ofdiscarded coil of an electric heater.)Touch the wire. Now switch on thecurrent in the circuit by moving theswitch to the ‘ON’ position. After a fewFig. 14.10CAUTIONDo not keep the switch in the ‘ON’position for a long time, otherwise thecell may become weak very quickly.seconds touch the wire. (Do not hold itfor a long time.) Switch off the current.Touch the wire again after a fewminutes.The wire gets hot when an electriccurrent passes through it. This is theheating effect of the electric current.Can you think of any electric appliancewhere the heating effect of the electriccurrent is used? Make a list of suchappliances.You might have seen an electricroom heater or an electric heater usedfor cooking. All these contain a coil ofwire. This coil of wire is called anelement. You may have noticed thatwhen these appliances are switched onBoojho could not see element in anelectric iron. Paheli told him thatelectrical appliances, such asimmersion heaters, hotplates, irons,geysers, electric kettles, hair dryers,have elements inside them. Have youever seen the element in anyappliance?Fig. 14.11 Element of electric iron164SCIENCE