146N force used to pull a 350 wood block at constant speed by a rope making an angle of 50 degree with the horizontal. Find the coefficient of sliding friction

Answer 1

Rope up force = 146 sin 50
Rope horizontal pull force = 146 cos 50

weight down = 350 Newtons (I assume you mean Newtons not mass in kg)
net normal force on floor = 350 - 146 sin 50
friction force back = mu ( 350- 146 sin 50)
friction force = pull force
mu ( 350 - 146 sin 50) = 146 cos 50