twenty elecric bulbs are connected in series with the mains of a 22ov suply. after 1 bulb is fused ,the remaining 19 bulbs are again connected in series across the same mains .what will b the effect on illumination?
twenty elecric bulbs are connected in series with the mains of a 22ov suply. after 1 bulb is fused ,the remaining 19 bulbs are again connected in series across the same mains .what will b the effect on illumination?
Case 1. The connection raptures after the first bulb gets fuzed. Then the 19 bulbs will stop glowing because electric current will not flow across the bulbs.
Case2. The connection somehow is kept live my alternate wire then the brightness of the rest bulbs will increase.
Let’s see how
Let the bulbs have resistance R Ω,
When the bulbs were all glowing
Total resistance will be = 20R Ω
Current flowing through the circuit I = 220/(20R) = 11/R ampere
Power delivered by each bulb = I2R = (11/R)2R = 121R Watt
Now when one gets fused current through each bulb becomes 220/(19R)
Power delivered by each bulb then will be = I2R = (220/19R)2R = 134R Watt
Thus luminous intensity of each bulb will increase 134R/121R = 1.12 times
Case 1. The connection raptures after the first bulb gets fuzed. Then the 19 bulbs will stop glowing because electric current will not flow across the bulbs.
Case2. The connection somehow is kept live my alternate wire then the brightness of the rest bulbs will increase.
Let’s see how
Let the bulbs have resistance R Ω,
When the bulbs were all glowing
Total resistance will be = 20R Ω
Current flowing through the circuit I = 220/(20R) = 11/R ampere
Power delivered by each bulb = I2R = (11/R)2R = 121R Watt
Now when one gets fused current through each bulb becomes 220/(19R)
Power delivered by each bulb then will be = I2R = (220/19R)2R = 134R Watt
Thus luminous intensity of each bulb will increase 134R/121R = 1.12 times
