Question

a bus decreases its speed from 80 kilometre per hour to 60 km per hour in 6 seconds when brakes are applied its velocity decreases to 30 kilometre per hour in 3 seconds find the acceleration in both the case

Answer 1

Case I:

u = 80 kmph = 22.22 mps
v = 60 kmph = 16.66 mps
t = 6 s
a = (v - u)/t = (16.66 - 22.22)/6 = -0.9266 mps^2

Case II:

u = 16.66 mps
v = 30 kmph = 8.33 mps
t = 3 s
a = (v - u)/t = (8.33 - 16.66)/3 = -2.7766