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GUJCET · Physics · Alternating Current
A light bulb is rated at 200 W for a 220 V supply. Find the resistance of the bulb ?
- A \(220 \Omega\)
- B \(484 \Omega\)
- C \(242 \Omega\)
- D \(400 \Omega\)
Answer & Solution
Correct Answer
(C) \(242 \Omega\)
Step-by-step Solution
Detailed explanation
(C) \(242 \Omega\)
Power \(\mathrm{P}=\frac{\mathrm{V}^{2}}{\mathrm{R}}\)
\(\therefore \quad \mathrm{R}=\frac{\mathrm{V}^{2}}{\mathrm{P}}\)
\(\therefore \quad \mathrm{R}=\frac{(220)^{2}}{200}\)
\(\therefore \quad \mathrm{R}=242 \Omega\)
Power \(\mathrm{P}=\frac{\mathrm{V}^{2}}{\mathrm{R}}\)
\(\therefore \quad \mathrm{R}=\frac{\mathrm{V}^{2}}{\mathrm{P}}\)
\(\therefore \quad \mathrm{R}=\frac{(220)^{2}}{200}\)
\(\therefore \quad \mathrm{R}=242 \Omega\)
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