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प्रश्न
Why is the electric power from the generating station transmitted at high voltage?
उत्तर
The electric power from the generating station is transmitted at high voltage to minimise the loss of energy in the live wires.
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संबंधित प्रश्न
Name two safety devices which are connected to the live wire of a household electric circuit
The SI unit of energy is :
(a) joule
(b) coulomb
(c) watt
(d) ohm-metre
The coil of an electric bulb takes 40 watts to start glowing. If more than 40 W are supplied, 60% of the extra power is converted into light and the remaining into heat. The bulb consumes 100 W at 220 V. Find the percentage drop in the light intensity at a point if the supply voltage changes from 220 V to 200 V.
Of the three connecting wires in a household circuit: Which two of the three wires are at the same potential? In which of the three wires should the switch be connected?
I ampere of current is passed through a resistor of resistance R ohm for time t second. Obtain expression for
(i) the electrical energy, and
(ii) the electrical power spent.
What is the resistance of an appliance rated at V volt, P watt?
An electric bulb is rated as 100W – 250V. What information does it convey? Calculate the current through the filament of the bulb.
A battery of e.m.f. 12V and internal resistance 1.6 Ω is connected to two resistors of 4Ω and 6Ω connected in parallel. Calculate:
(i) the current drawn from the battery,
(ii) the power dissipated in each resistor,
(ii)the total power supplied by the battery.
Compare the power used in the 2 Ω resistor in each of the following circuits:
- a 6 V battery in series with 1 Ω and 2 Ω resistors
- a 4 V battery in parallel with 12 Ω and 2 Ω resistors.
