Two 220-volt, 100-watt bulbs are connected first in series and then in parallel. Each time the combination is connected to a 220-volt a.c. supply line. The power drawn by the combination in each case respectively will be:
Two 220-volt, 100-watt bulbs are connected first in series and then in parallel. Each time the combination is connected to a 220-volt a.c. supply line. The power drawn by the combination in each case respectively will be:
50 watt,100 watt
100 watt,50 watt
200 watt,150 watt
50 watt,200 watt
The Correct Option is D
Solution and Explanation
If rated voltage = supply voltage then use
\(\frac{1}{P}=\frac{1}{P_1}+\frac{1}{P_2}\) (series connection) & P = P1 + P2 (parallel connection)
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Concepts Used:
Electric Power
Power is defined as the rate of doing work. Electric power is the rate at which electrical energy is transferred through an electric circuit, i.e. the rate of transfer of electricity. The symbol for Electric Power is ‘P’. SI unit of electric power is Watt.
Electric Power Formula
P = VI
From Ohm's Law, V = IR
Hence, Power can also be expressed as P = I2R