Question

trolley while, going down an inclined plane ,has an acceleration of 2 cm s-² .what will be its velocity 3 s after the start?

Answer 1

a=0,02cm/s
t=3s
by equation of motion if it starts  from rest u=0m/s
v=at 
  =.02*3
     =.06m/s

Answer 2

Let initial velocity be x cm/s .
Then acc. To equation
v=u +at
Where v= final velocity.
u=initial velocity=x cm/s
a=acceleration.
& t=time.
Then v after 3 seconds will be
v=x + 2*3.
v=(x + 6)cm/s.
Note initial and final velocities are in cm/s