If the tension in the string in figure (6-E3) is 16 N and the acceleration of each block is 0.5 m/s2, find the friction coefficients at the two contacts with the blocks.
The free body diagram of the given problem is shown above.
From figure (a)
μ1R + ma = T
μ1R + 2(0.5) = 16 {R = mg cosθ}
⇒ μ1(2g) =15
⇒ μ1 = 0.75
From figure (b)
μ2R + ma = F − mg sin θ
⇒μ2mg cos θ + 4 (0.5) = 16 − 4g sin 30°
⇒μ2 = 0.06