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The Specification on a Heater Coil is 250 V, 500 W. Calculate the Resistance of the Coil. What Will Be the Resistance of a Coil of 1000 W to Operate at the Same Voltage? - Physics

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प्रश्न

The specification on a heater coil is 250 V, 500 W. Calculate the resistance of the coil. What will be the resistance of a coil of 1000 W to operate at the same voltage?

बेरीज
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उत्तर

Let R be the resistance of the coil.

The power P consumed by a coil of resistance R when connected across a supply V is given by

\[P = \frac{V^2}{R}\]

\[ \Rightarrow R = \frac{V^2}{P}\]

\[ \Rightarrow R = \frac{\left( 250 \right)^2}{500} = 125 \Omega\]

Now, P = 1000 W

\[\Rightarrow R = \frac{V^2}{P} = \frac{\left( 250 \right)^2}{1000} = 62 . 5 \Omega\]

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पाठ 11: Thermal and Chemical Effects of Current - Exercises [पृष्ठ २१८]

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एचसी वर्मा Concepts of Physics Vol. 2 [English] Class 11 and 12
पाठ 11 Thermal and Chemical Effects of Current
Exercises | Q 3 | पृष्ठ २१८

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