Question

A car starts from rests and coasts down a hill with a constant accelaration. If it goes 90 meters in 8 seconds, find the acceleration and the velocity after 8 seconds

Answer 1

It start from rest so
U,Initial velocity=0
Distance,s=90
Time,t=8
a,acceleration=?
v,velocity or final velocity=?

so in eq2..
s=ut+1/2at²
90=0×8+1/2a(8)²
90=0+1/2a64
90=a32
a=90/32
a=2.8125

Our acceleration is 2.8125

using Eq1 to find velocity
v=u+at
v=0+2.8125×8
v=22.5
so our velocity is 22.5.

Hence we find acceleration,a that is 2.8125 and velocity after 8 seconds is 22.5