A body is dropped from a height of 20 m. Its velocity on reaching ground (g=10) is MCQ with Answer and Explanation

A body is dropped from a height of 20 m. Its velocity on reaching ground (g=10) is
A. 40 m/s
B. 10 m/s
C. 20 m/s
D. 14.14 m/s
Answer: Option C
Solution (By JKSSB Mock Tests)
v² = 2gh = 2×10×20=400, v=20 m/s.

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Which scientist famously demonstrated that a changing magnetic field induces an electromotive force (EMF), discovering electromagnetic induction?
A. Heinrich Lenz
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C. Nikola Tesla
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Correct Answer: Option B


Explanation:
Michael Faraday discovered electromagnetic induction. He showed that moving a magnet through a coil of wire, or changing the magnetic flux in one coil near another, induces an electrical current. Lenz's law later described the direction of that induced current. Maxwell formulated the classical theory of electromagnetic radiation.

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Correct Answer: Option A


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Torque dimensions same as:
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Correct Answer: Option C


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