Question

when a car driver travelling at a speed of 10m/s applies brakes and brings the car to rest in 20s, then the acceleration will be:
(a) +2m/s^2
(b) -2m/s^2
(c)-0.5m/s^2
(d) +0.5m/s^2​

Answer 1

Answer is (c)
U=10
t=20
V=0
a=?
V=u+at
0=10+20a
-20a=10
a=-10/20=-0.5m/s^2