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Question
Figure shows two circuits each having a galvanometer and a battery of 3V.
When the galvanometers in each arrangement do not show any deflection, obtain the ratio R1/R2.
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Solution
For balanced wheat stone bridge, there will be no deflection in the galvanometer.
`4/R_1 = 6/9 => R_1 =(4 xx 9)/6 = 6Ω`
For the equivalent circuit, when the wheat stone bridge is balanced, there will be no deflection in the galvanometer.
`therefore 12/8 = 6/R_2 => R_2 \ ( 6xx 8)/12 = 4 Ω`
`therefore R_1/R_2 = 6/4 = 3/2`
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