A mechanic is reinstalling a newly-sharpened blade on a lawn mower. A wedged-in block of wood at C prevents the blade from rotating as the 34-lb force is applied to the wrench handle. The blade is bolted to a bracket attached to the motor shaft O, which protrudes through the bracket and blade. Determine the normal force at C. State any assumptions. Does it matter whether the bolt at B is installed?

A mechanic is reinstalling a newly-sharpened blade on a lawn mower. A wedged-in block of wood at C prevents the blade from rotating as the 34-lb force is applied to the wrench handle. The blade is bolted to a bracket attached to the motor shaft O, which protrudes through the bracket and blade. Determine the normal force at C. State any assumptions. Does it matter whether the bolt at B is installed?