Q11 of 41 Page 221

Show how you would connect three resistors, each of resistance 6, so that the combination has a resistance of (i) 9, and (ii) 4 .

(i) In order to get a resistance of 9 from three resistors of 6 each, we connect two 6 resistors in parallel and then this parallel combination is connected in series with the third 6 resistor .


For parallel connection:


Or R= 3


And for series connection: R= 3 + 6= 9


(ii) In order to get a resistance of 4 from three resistors of 6 each, we connect all the three 6 resistors in parallel:




Or R= 2


Then, Net Resistance R= 2+ 2= 4.


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