A System of Blocks and a Frictionless Pulley Is Shown

question 68

Multiple Choice

A system of blocks and a frictionless pulley is shown in the figure.Block A has a mass of 2.0 kg and is on a rough horizontal surface for which μ_s = 0.40 between the surface and block A.The rope pulls horizontally on block A.Block C has a mass of 1.0 kg.An external force P = 23.0 N,applied vertically to block A,maintains the system at rest as shown in the figure.What is the friction force on block A?

• A) 6.3 N
• B) 6.9 N
• C) 7.5 N
• D) 5.7 N
• E) 5.1 N