A torque of a circular rotating body is calculated by multiplying the force acting on the centre with it's lever arm. If this force acts at an angle like the one we have in the question, we derive our resultant force and use it in our calculations.
F = 60N
Angle = 75°
Sin 75 = 0.9659
Lever arm = 12cm = 0.12m.
Deriving the resultant torque from the given angle becomes:
