Question

a car starts from rest and moves with a uniform acceleration of 1m/s square for 10 seconds. it then moves with a uniform velocity for 30 seconds. the brakes are then applied and the car is brought to rest in 10 seconds. find the total distance covered by the car.

Answer 1

part 1

u=0 m/s
t= 10 secs
a= 1 m/s^2

s1=ut+ 0.5at^2
v=u+at

part 2

a=0 m/s^2
u=v( from part 1)
t=30 secs

s2= v*t

part 3

final speed of part 2 equals initial speed of part 3
v=0 m/s

t=10 s

a= -u/t
s3=ut+0.5at^2

total distance covered = s1+s2+s3

Answer 2

Here is a shorter solution of this as slope of v-t graph is acceleration and area is displacement