QQuestion
5 bulbs are connected in series in a room. One bulb is fused. It is removed and remaining 4 bulbs are again connected in series to the same circuit. What will be the effect on the following physical quantities? (Increases, Decreases, Remain Same)
(a) Resistance
(b) Intensity of light
✓Answer
(a) In a series connection, total resistance is the sum of individual resistances.
Let resistance of each bulb be R.
Initially :
Rtotal = 5R
After removing one bulb:
Rtotal = 4R
So, resistance will decrease.
(b) When resistance decreases, total current in the circuit (assuming the same voltage supply) will increase :
I = V/R
So, more current → more power delivered to each bulb.
Since,
Power (P) = I2R,
Hence, intensity of light increases for each remaining bulb.
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