Question

A body of mass 2kg is at rest at the origin of farme of reference .A force of 5N acts on it at t=0. The force acts for 4s and then stops.

1.what is the acceleration produced by the force on the body?
2.what is the velocity at t=4s
3.Draw the vt graph for the period t=0 to t=6s.
4.Find the distance travelled in 6s.

Answer 1

Explanation:

1. F = m×a

5=2×a

a=5÷2

a=2.5

2. v=u+at

u=0 , a= 2.5 , t=4

v =0+2.5×4

v=10

4. s=ut+1/2 at^2

0+1/2× 2.5×6×6

s= 1.8m

Answer 2

as the body starts from rest u = 0
F = ma
5 = 2×a
a = 5÷2= 2.5m/s^2

v = u + at
v = 0 + (2.5)×4 =10m/s

S = ut + 1/2at^2
S = 0 + 1/2×2.5×6×6
= 45m