Q108 / 180 · AIIMS 2008 · Physics
A bulb of \(25 \mathrm{~W}, 200 \mathrm{~V}\) and another bulb of \(100 \mathrm{~W}, 200 \mathrm{~V}\) are connected in series with a supply line of \(220 \mathrm{~V}\). Then
- Aboth bulbs will glow with same brightness
- Bboth bulbs will get fused
- Correct answerC\(25 \mathrm{~W}\) bulb will glow more brightly
- D\(100 \mathrm{~W}\) bulb will glow more brightly.
Solution
Resistance of $25 \mathrm{~W}, 200 \mathrm{~V}$ bulb
$R_1=\frac{(200)^2}{25} \Omega$
Resistance of $100 \mathrm{~W}, 200 \mathrm{~V}$ bulb
$R_2=\frac{(200)^2}{100} \Omega$.
Clearly, $R_1>R_2 . \quad \therefore \quad H_1>H_2$.
$\therefore 25 \mathrm{~W}$ bulb will glow more brightly.
Hence, the correct answer is option: 'C'.