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Two Bulbs Are Marked 60 W, 220 V and 60 W, 110 V Respectively. Calculate the Ratio of Their Resistance.

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Question

Two bulbs are marked 60 W, 220 V and 60 W, 110 V respectively. Calculate the ratio of their resistance.
Numerical
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Solution

We know that R = `"V"^2/"P"`

`"Resistance of 60 W-220 V bulb"/"Resistance of 60 W-220 V bulb" = (220)^2/60 x 60/(110)^2 = 4/1`

Thus, the required ratio is 4: 1.

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Chapter 4: Electricity and Magnetism - Exercise 5 [Page 213]

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Frank Physics Part 2 [English] Class 10 ICSE
Chapter 4 Electricity and Magnetism
Exercise 5 | Q 4 | Page 213

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