Block A of mass 1 kg is kept on block B of mass 2kg which is kept on smooth surface as shown in figure. At t = 0 both blocks are at rest and a force of 6N is applied on block B. Friction coefficient between A and B is 0.5. Which of the following is/are correct :-

Question

G1 Physics · Accepted Answer

For the combined 3 kg system, a=6/3=2 m/s². The top 1 kg block therefore needs friction f=ma=2 N. At t=2 s, v=4 m/s and K(A)=½(1)(4²)=8 J. Friction does positive work on A, so B is false. Hence A,C,D.