A palm fruit dropped to the ground from the top of a tree 45m tall. How long does it take to reach the ground?

John Perolski
August 09, 2023

Physics Jamb, Waec, Neco Past Questions & Answers on Speed, Velocity and Acceleration

QUESTIONS 42. A palm fruit dropped to the ground from the top of a tree 45m tall. How long does it take to reach the ground? [g=10m/s²] 

  • A. 9s 
  • B. 4.5s 
  • C. 6s 
  • D. 7.5s 
  • E. 3s 

JAMB 1978 Ans: 3s


SOLUTIONS 

  • Initial velocity u, 0m/s
  • Final velocity v, = ?
  • Height h, 45m
  • Acceleration due to gravity g, 10m/s²
  • Time taken t to reach the ground =?


Using h = ut + ½gt²

45 = 0xt + ½(10)t²

45 = 0 + 10/2t²

45 = 5t²

45/5 = t²

t² = √9

t = 3s