Question

2. A body of mass 20 kg is moving in a straight line with a constant velocity of 10 metre per second. The
external force applied on it is...
IM
A. 200N
B.0
C.4N
D.20N
​

Answer 1

Explanation:

Force =m

t

(v−u)

=m⋅a

Displacement =

2a

(v

2

−u

2

)

Word done (W) = Force × Displacement

=m⋅a⋅

2a

(v

2

−u

2

)

W =

2

1

m(v

2

−u

2

)

W =

2

1

×20×(2500−1600)

=

2

1

×20×900

=9000J

Therefore, the work done to attain the final velocity is 9000J

Answer 2

Answer:

the answer is in the form of 0