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2 years ago

What is the resistance of a bulb of 40w connected in a line of 70v

Physics

1 answer:

olga55 [171]2 years ago

4 0

Answer:

122.5 ohm

Explanation:

Given :

P=40 w

V= 70 V

R=?

Resistance can be calculated as :

$P=\frac{V^{2} }{R} \\40=\frac{(70)^{2} }{R}\\40=\frac{4900}{R} \\R=\frac{4900}{40} \\R=122.5 ohm$

Therefore, resistance of the bulb will be 122.5 ohm

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Answer:

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Explanation:

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