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Karnataka Board PUCPUC Science 2nd PUC Class 12

Power P is to be delivered to a device via transmission cables having resistance RC. If V is the voltage across R and I the current through it, find the power wasted and how can it be reduced.

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Question

Power P is to be delivered to a device via transmission cables having resistance RC. If V is the voltage across R and I the current through it, find the power wasted and how can it be reduced.

Short/Brief Note
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Solution

Power wasted PC = I2RC

Where RC is the resistance of the connecting wires.

`P_C = P^2/V^2 R_c`

In order to reduce PC, power should be transmitted at high voltage.

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Chapter 3: Current Electricity - MCQ I [Page 19]

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NCERT Exemplar Physics Exemplar [English] Class 12
Chapter 3 Current Electricity
MCQ I | Q 3.18 | Page 19

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