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www.GOALias.blogspot.comthat the rubber bands hold the metalstrips tightly.You could also buy cell holders fromthe market for making batteries of twoor more electric cells. Place the cells inthem properly, such that the positive162Fig. 14.4 A cell holderFig. 14.5 Holder for battery of two cellsPaheli and Boojho wonder whetherthe batteries used in tractors, trucksand inverters are also made from cells.Then why is it called a battery? Canyou help them to find the answer tothis question?Fig. 14.6 Truck battery and its cutoutterminal of one cell is connected to thenegative terminal of the next cell.Connect a piece of wire each to the twometal clips on the cell holder as shownin Fig.14.5. Your battery is ready for use.The symbol used for representing abattery is shown in Table.14.1. It hasthree cells. Therefore, it has three pairsof long and short parallel lines.Let us now draw a circuit diagram ofan electric circuit using symbols shownin Table 14.1.Activity 14.1Make the electric circuit shown inFig. 14.7. You used a similar circuit inClass VI to make an electric bulb glow.Do you remember that the bulb glowsonly when the switch is in the ‘ON’position? The bulb glows as soon as theswitch is moved to the ‘ON’ position.Copy this electric circuit in yournotebook. Make also a circuit diagramof this circuit using symbols for thevarious electric components.Is your diagram similar to the oneshown in Fig. 14.8?It is much easier to draw a circuitdiagram using symbols. Therefore, wegenerally represent an electric circuit byits circuit diagram.Fig. 14.9 shows another circuitdiagram. Is it identical to the circuitdiagram shown in Fig.14.8? In whichway is it different?Would the bulb glow in this electriccircuit? Recall that the bulb glows onlywhen the switch is in the ‘ON’ positionand the electric circuit is closed.SCIENCE