The potential at a point due to a point charge is 10 V at distance 2 m. Potential at 4 m is MCQ with Answer and Explanation

The potential at a point due to a point charge is 10 V at distance 2 m. Potential at 4 m is
A. 10 V
B. 2.5 V
C. 20 V
D. 5 V
Answer: Option D
Solution (By JKExamLibrary)
V ∝ 1/r. So if r doubled, V halved = 5 V.

This question belongs to: Science Physics

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The unit of mutual inductance is
A. Henry
B. Weber
C. Farad
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Correct Answer: Option A


Explanation:
Mutual inductance M = emf/(di/dt), unit Henry.

This question belongs to: Science Physics
Question #2 Report Error
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Correct Answer: Option B


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This question belongs to: Science Physics
Question #3 Report Error
According to the principle of homogeneity of dimensions, in an equation A = B + C, what must be true about the dimensions of A, B, and C?
A. A, B, and C must all have identical dimensions.
B. B and C must be dimensionless.
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Correct Answer: Option A


Explanation:
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This question belongs to: Science Physics