A ball is dropped from a height of 20 m. Time to reach ground (g=10) is MCQ with Answer and Explanation

A ball is dropped from a height of 20 m. Time to reach ground (g=10) is
A. 2 s
B. 1 s
C. 3 s
D. 4 s
Answer: Option A
Solution (By JKSSB Mock Tests)
h = ½gt² => t = √(2h/g) = √(40/10) = √4 = 2 s. Free fall formula. Final velocity v = gt = 20 m/s.

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Polarization of light confirms that light is
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B. Both
C. Neither
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Correct Answer: Option D


Explanation:
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This question belongs to: Science Physics
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Correct Answer: Option C


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The phenomenon of polarization is used in:
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Correct Answer: Option C


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