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www.GOALias.blogspot.com1414 Electric Current and itsEffectsYou might have tried the game‘How steady is your hand?’suggested in Chapter 12 ofClass VI. If not, you may try it out now.Paheli and Boojho had also set up thegame by connecting an electric circuitas suggested in Class VI. They had lotsof fun trying it out with their familiesand friends. They enjoyed it so muchthat they decided to suggest it to acousin of theirs who stayed in adifferent town. So, Paheli made a neatdrawing showing how the variouselectric components were to beconnected (Fig.14.1).Fig. 14.1 Setup to check how steadyyour hand isCan you draw this circuitconveniently? It made Boojho wonder ifthere was an easier way to representthese electric components.14.1 S14.1 SYMBOLSOF ELECTRICCOMPONENTSSome common electric components canbe represented by symbols. In Table 14.1,some electric components and theirsymbols are shown. You may comeacross different symbols for thesecomponents in different books. However,in this book, we shall be using thesymbols shown here.Look at the symbols carefully. In thesymbol for the electric cell, notice thatthere is a longer line and a shorter butthicker parallel line. Do you recall thatan electric cell has a positive terminaland a negative terminal? In the symbolof the electric cell, the longer linerepresents the positive terminal and thethicker, shorter line represents thenegative terminal.For a switch the ‘ON’ position andthe ‘OFF’ position are represented by thesymbols as shown. The wires used toconnect the various components in acircuit are represented by lines.In Table 14.1, a battery and itssymbol are also shown. Do you knowwhat a battery is? Look at the symbol ofa battery. Can you make out what abattery could be? For some of theactivities we may need more than onecell. So, we connect two or more cellstogether as shown in Fig.14.2. Notice160SCIENCE