Solution:
Key Concept: Power loss due to transmisssion lines having resistance (R) and Irms current flowing in the circuit is I2rms R.
The power is to be transmitted over the large distances ar high alternating voltages, so current flowing through the wires will be low because of given power (P).
For a given power level, we find that
P = ErmsIrms (Irms is low when Erms is high)
Powor loss = I2rms R = low ($\because$ Irms is low)
Now at the receiving end high voltage is reduced by using step-down transformers.
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(a) Q = |
(b) Q = |
(c) Q = |
(d) Q = |
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(a) |
(b) |
(c) |
(d) |
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The inductance of a closed-packed coil of 400 turns is 8 mH. A current of 5 mA is passed through it. The magnetic flux through each turn of the coil is
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(a) |
(b) |
(c) |
(d) |
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(a) If both assertion and reason are true and the reason is the correct explanation of the assertion. |
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(c) If assertion is true but reason is false. |
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(d) If the assertion and reason both are false. |
