A stone is dropped from the top of a tower. The distance covered in the last second is 36 m. Taking g = 10 m s⁻², the total time of fall is:
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A stone is dropped from the top of a tower. The distance covered in the last second is 36 m. Taking g = 10 m s⁻², the total time of fall is:

G1 Physics · Accepted Answer

For total time T, distance in the last second = (g/2)[T² − (T − 1)²] = 5(2T − 1). Set 5(2T − 1) = 36 ⇒ 10T = 41 ⇒ T = 4.1 s.