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प्रश्न
What is meant by "electric power"?
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उत्तर
The energy required per unit of time is called electrical power.
संबंधित प्रश्न
What is the maximum power in kilowatts of the appliance that can be connected safely to a 13 A ; 230 V mains socket?
The commercial unit of energy is :
(a) watt
(b) watt-hour
(c) kilowatt-hour
(d) kilo-joule
How much energy does a 100 W electric bulb transfer in 1 minute?
(a) 100 J
(b) 600 J
(c) 3600 J
(d) 6000 J
Explain why, filament type electric bulbs are not power efficient.
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?
An electric toaster draws 8 A current in a 220 V circuit. It is used for 2 h. Find the cost of
operating the toaster if the cost of electrical energy is Rs. 4.50 per kWh.
A geyser is rated 1500 W, 250 V. This geyer is connected to 250 V mains. Calculate:
(i) the current drawn
(ii) the energy consumed in 50 hours, and
(iii) the cost of energy consumed at Rs. 4.20 per kWh
A bulb with rating 250 V, 100 W is connected to a power supply of 220 V situated 10 m away using a copper wire of area of cross-section 5 mm2. How much power will be consumed by the connecting wires? Resistivity of copper = 1.7 × 10−8 Ωm
Fig . shows the essent ial features of a battery operated bell. The hammer strikes the gong when the swi tch is closed . State and explain the effect of using the following material successively to form the core.
(a) Plastic
(b) Steel
(c) Copper
In an electric radiator or room heater, state with reason, why the porcelain tube wound with a nichrome wire is placed between the pole and principal focus of the parabolic concave reflector.
Why does not the heating coil produce any visible light? in an electric stove.
An electric bulb is marked 100 W, 230 V. What does this mean?
Three 250 W heaters are connected in parallel to a 100 V supply, Calculate total current taken from the supply.
State (i) the S. I. unit, (ii) the household unit, of electrical energy. How are these units related?
Find the energy released by a current of 0.25 amperes flowing through a heater for 5 minutes. The p.d. is 230 V.
An Electric bulb is marked 100 W, 230 V. What current does it take?
The equation I2R seems to suggest that the rate of heating in a resistor is reduced if resistance decreases, whereas equation P = V2/R suggests just the opposite. How do you reconcile this problem?
The electrical power and current in the circuit relates by ______
Two heaters A and B have power rating of 1 kW and 2 kW, respectively. Those two are first connected in series and then in parallel to a fixed power source. The ratio of power outputs for these two cases is ______
