A body starts from rest and accelerates uniformly at 5m/s² until it attains a velocity of 25m/s. Calculate the time taken to attain this velocity.

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

QUESTIONS 4. A body starts from rest and accelerates uniformly at 5m/s² until it attains a velocity of 25m/s. Calculate the time taken to attain this velocity.

WAEC 2005 Ans: 5s

SOLUTIONS:

Starts from rest = initial velocity = u = 0m/s

Acceleration= a = 5m/s²

Final velocity = v = 25m/s 

Time taken = t = ?

Using first equation of motion

v = u + at

25 = 0 + 5(t)

25 - 0 = 5t

25 = 5t

t = 25/5

t = 5s Answer