JEE Mains · Physics · STD 12 - 3. current electricity
An electric bulb of \(500 \,watt\) at \(100\, volt\) is used in a circuit having a \(200\, {V}\) supply. Calculate the resistance \({R}\) to be connected in series with the bulb so that the power delivered by the bulb is \(500\, {W}\). (in \(\Omega\))
- A \(20\)
- B \(30\)
- C \(5\)
- D \(10\)
Answer & Solution
Correct Answer
(A) \(20\)
Step-by-step Solution
Detailed explanation
\({P}={Vi}\) \(500={Vi}\) \({i}=5 {Amp}\) \({V}={i} \times {R}\) \({R}=20\)
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