Question

Velocity-time graph of a particle of mass (2 kg) moving in a straight line is as shown in Fig. 9.20. Find the word done by all the forces acting on the particle. .
A. 400 J
B. `-400 J`
C. `-200 J`
D. 200 J

Answer 1

Correct Answer - B
(b) Work done by all forces = change in kinetic energy
`=(1)/(2)m(v_(f)^(2)-v_(i)^(2))=(1)/(2)xx2(0-400)=-400J`