Search SchoolNGR

Monday, 06 July 2026
Register . Login

A stone was dropped from the top of a building 40m high. Find, correct to one decimal ...

A stone was dropped from the top of a building 40m high. Find, correct to one decimal place, the time it took the stone to reach the ground. [Take g = 9.8ms\(^{-2}\)]
Take Free Practice Test On 2026 JAMB UTME, Post UTME, WAEC SSCE, GCE, NECO SSCE
  • A 2.9.seconds
  • B 2.8 seconds
  • C 2.6 seconds
  • D 1.4 seconds
Correct Answer: Option A
Explanation:
s = \(\frac{1}{2}gt^2\)
40 = \(\frac{1}{2} \times 9.8 \times t^2\)
\(\frac{80}{9.8} = t^2\)
t = \(\sqrt{8.16326}\)
t 2.9 secs

Share question on: