JEE Main 2016 · 10 Apr · Shift 1 · Physics Q4

PhysicsSingle correct+4 / -1Question 4 of 90

Velocity-time graph for a body of mass 10 kg is shown in figure. Work-done on the body in first two seconds of the motion is :

12000 J

−12000 J

−4500 J

−9300 J

Answer and worked solution

Official answer: C

v falls linearly from 50 to 0 in 10 s, so at t = 2 s, v = 40 m/s. By the work-energy theorem,
$W=\tfrac12\times10\,(40^2-50^2)=-4500\text{ J}.$

JEE Main 2016 · 10 Apr · Shift 1, Physics question 4