1. Tardigrade
  2. Question
  3. Physics
  4. Three bulbs of 40 W, 60 W and 100 W are arranged in series across a 220 V supply. The bulb giving maximum brightness is of

Question Error Report

Thank you for reporting, we will resolve it shortly

Back to Question

Q. Three bulbs of $40 \,W, 60\, W$ and $100 \,W$ are arranged in series across a $220\, V$ supply. The bulb giving maximum brightness is of

Rajasthan PMTRajasthan PMT 2003

Solution:

When bulbs are connected in series, the current in each bulb remains same. As power $P=i^{2} R$, so, the bulb having maximum resistance will appear brightest.
The resistance of a bulb,
$R=\frac{V^{2}}{P} \propto \frac{1}{P} $ (For same $ V $)
$\therefore $ The bulb of least power possesses maximum resistance.
Hence, $40\, W$ bulb will appear brightest when connected in series with other bulbs.