Question

car initially at rest starts with A uniform acceleration and gains a velocity of 20 m per second in 4 seconds The displacement of the car is

Answer 1

u = 0m/s as it is at rest
v = 20m/s (given)
t = 4 secs
First,
v=u+at
20 = 0 + 4a
a = 20/4
= 5m/s^2
Now,
s = ut + 1/2at^2
= 0 + 1/2*5*4*4
= 5*4*2
= 40 m

Answer 2

u= 0m/s

v= 20m/s

t= 4s

a= v2-v1/t= 5m/s^2

s= ut+1/2at^2

s=0+1/2×5×4×4

∴s=40m