Finding the magnitude of Torque

[nina123]

Homework Statement

A force F = 75.0 N is applied to a box with dimensions y = 2.51 m, x = 1.62 m. The force is applied at an angle θ with respect to the horizontal. For θ = 35.0°, calculate the magnitude of the torque produced by F about the point O.
(reference attached picture)

Homework Equations

t=rFsinθ=r$\bot$F=rF$\bot$

The Attempt at a Solution

For the other questions like this i just used t=rF when the angles were 0 and 90deg.
but now that it is at a 35deg angle the same formula doesn't work.

HELP PLEASE?

 

[Sourabh N]

In your formula for the torque, the angle θ corresponds to the angle between the radial vector (connecting the points O and F) and the direction of the force.
In your image, draw this radial vector and then you can see what the angle between the radial vector and the force is. Use this angle in the formula.

 

[nina123]

Thanks!