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संबंधित प्रश्न
An electric fan runs from the 230 V mains. The current flowing through it is 0.4 A. At what rate is electrical energy transferred by the fan?
An electric heater is rated at 2 kW. Electrical energy costs Rs 4 per kWh. What is the cost of using the heater for 3 hours?
(a) Rs 12
(b) Rs 24
(c) Rs 36
(d) Rs 48
State whether an electric heater will consume more electrical energy or less electrical energy per second when the length of its heating element is reduced. Give reasons for your answer.
Electrical power p is given by the expression P = (Q × V) ÷ time. Express the power P in terms of current and resistance explaining the meaning of symbols used there in.
Distinguish between kilowatt and kilowatt-hour.
A current of 2 A is passed through a coil of resistance 75Ω for 2 minutes. (a) How much heat energy is produced? (b) How much charge is passed through the resistance?
Two bulbs are rated 60 W, 220 V and 60 W, 110 V respectively. Calculate the ratio of their
resistances
What does the unit kilowatt hour measure? Define it.
The unit of e.m.f. of a cell is ____________.
