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Electric Current Physics Current Electricity Physics Class 12th

The ratio of the equivalent resistance of the network (shown in figure) between the points a and b when switch is open and switch is closed in x : 8. The value of x is_________.

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alok kumar singh | Contributor-Level 10

2 months ago

When switch is open,

$R_{e q} = \frac{3 R}{2}$

When switch is closed,

$R_{e q}^{'} = 2 \times \frac{R \times 2 R}{R + 2 R} = \frac{4 R}{3}$

$\frac{R_{e q}}{R_{e q}^{'}} = \frac{3 R / 2}{4 R / 3} = \frac{9}{8} = \frac{x}{8}$

$\Rightarrow x = 9$

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The ratio of the equivalent resistance of the network (shown in figure) between the points a and b when switch is open and switch is closed in x : 8. The value of x is_________.

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