A body falls freely under gravity (g=9.8m/s²) from a height of 40m on to the top of a platform 0.8m above the ground. It’s velocity on reaching the platform is

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

QUESTIONS 37. A body falls freely under gravity (g=9.8m/s²) from a height of 40m on to the top of a platform 0.8m above the ground. It’s velocity on reaching the platform is

A. 784ms- B. 80ms' C. 78.4ms' D. 39.2ms'¹ E. 27.7ms'

JAMB 1981 Ans: 27.7ms 1

SOLUTIONS 

acceleration due to gravity g= 9.8m/s²

Height h= 40m - 0.8 = 39.2 platform 0.8m above ground level 

Final velocity v= ?

Using v ² = u² + 2as

V² = 0² + 2(9.8)(39.2)

v² = 0 + 19.6 (39.2)

v² = 768.32

v= √768.32

v = 27.72m/s