A ball is thrown upward with velocity 30 m/s. Time to reach maximum height (g=10) is MCQ with Answer and Explanation

A ball is thrown upward with velocity 30 m/s. Time to reach maximum height (g=10) is
A. 1.5 s
B. 2 s
C. 6 s
D. 3 s
Answer: Option D
Solution (By JKSSB Mock Tests)
v = u - gt, at top v=0 => t = u/g = 30/10 = 3 s.

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Question #1
A student measures length as 3.600 cm using vernier calliper of least count 0.001 cm. Number of significant figures is
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B. 4
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Correct Answer: Option B


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A wire of resistance 10 Ω is stretched to double its length. Its new resistance is
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Correct Answer: Option B


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Critical angle for glass (n=1.5) to air:
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Correct Answer: Option C


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