The coefficients of friction between the block and the rail are s = 0.25 and

The coefficients of friction between the block and the rail are μ_s = 0.25 and μ_k = 0.20. Knowing that θ = 60°, determine the smallest value of P required 

(a) To start the block moving up the rail,

(b) To keep it moving up,

(c) To prevent it from moving down.

Transcribed Image Text:

135⁰ 600 N Fig. P8.9 and P8.10 P