How Do You Calculate Torque When Force is Applied at an Angle?

[Kamikaze]

Homework Statement

A Force F = 76.0N is applied to a box with dimensions y = 2.69m, x = 1.04m. The force is applied at an angle theta with respect to the horizontal as shown. For theata = 24.0 deg, calculate the magnitude of the torque produced by F about the point O.

Homework Equations

T=r(Fperpendicular)
Fperpendicular = Fsin(theta)

The Attempt at a Solution

I did pythagorean theorem (a2 + b2 = c2) to find the diagonal (r) at 2.88404m
I then found Fperpendicular by using Fperpendicular = 76Nsin(24deg) = -68.823956N . I then multiplied this by the r I found earlier to find the magnitude of Torque at -198.4911991N. Somehow this is wrong and I don't know how else to do it.

 

[tiny-tim]

Welcome to PF

Hi Kamikaze! Welcome to PF

(have a theta: θ and a degree: ° and try using the X² tag just above the Reply box )

I then found Fperpendicular by using Fperpendicular = 76Nsin(24deg)

wrong angle!

useful tip: always draw your diagrams fully … if you'd put in the extra lines, you'd see it isn't θ.