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Current Electricity — Physics STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 SciencePhysicsCurrent Electricity1 Mark
Question
For two statements are given-one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below.
  1. Both A and R are true, and R is the correct explanation of A.
  2. Both A and R are true, but R is not the correct explanation of A.
  3. A is true, but R is false.
  4. A is false, and R is also false.
Assertion: It is advantageous to transmit electric power at high voltage.
Reason: High voltage implies high current.
✓

Answer

  1. A is true, but R is false.
Explanation:
As P = Vi, hence for the transmission of same power, high voltage implies less current. Therefore heat energy loses $\Big(\text{H} = \frac{\text{i}^2\text{Rt}}{4.2}\Big)$are minimized if power is transmitted at high voltage.

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