In the shown system m₁ = 20 kg, m₂ = 5 kg and M = 50 kg. The ground under M is smooth; the coefficients of friction between m₁ and M and between m₂ and ground are 0.3. For the specified condition f₁ = 2f₂, which results are correct?

Question

G1 Physics · Accepted Answer

Writing Newton's equations for m₁, m₂ and M with f₁=2f₂ and the common-string constraint gives a = 3/5 m s⁻². The same equations give tension T = 18 N and applied force F = 60 N. Hence A, B and C are correct.