If a stone dropped from the top of a tower reaches the ground in 4 seconds, what is the approximate height of the tower? (Take g = 10 m/s²) MCQ with Answer and Explanation

If a stone dropped from the top of a tower reaches the ground in 4 seconds, what is the approximate height of the tower? (Take g = 10 m/s²)
A. 60 m
B. 80 m
C. 40 m
D. 160 m
Answer: Option B
Solution (By JKSSB Mock Tests)
Using the second equation of motion for free fall: h = ut + ½gt². Since it is dropped, initial velocity (u) = 0. Time (t) = 4s, g = 10 m/s². The height h = 0 + ½(10)(4)² = 5 × 16 = 80 meters.

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