Question

7. A certain force acts on a body at rest. If after
10 seconds the body moves with a velocity of
20 m/s and if its mass is 3 kg, find the
magnitude of the force acting on the body.​

Answer 1

Explanation:

F= ma or m×(v-u) t

given

m = 3kg

u= 0 ( as body starts moving from rest)

v= 20m/s

t= 10 s

putting in formula we get

F= 3×(20-0)10

= 3× 20/10

F = 60/10 = 6N

Answer 2

Explanation:

F = ma

mass of body = 3kg

acceleration of body :-

(Final velocity - Initial Velocity) / time

Initial Velocity = 0m/s (Given body was at rest)

Final Velocity = 20m/s

Time taken = 10s

So acceleration will be,

a = (20 - 0) / 10

a = 2m/s²

Now, Put all values in Force Formula You get

F = ma

F = 3 x 2

F = 6N

So, force applied to move the object is 6N or Magnitude of Force applied is 6N