TPR Mechanics Question- Help please

[Iota]

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A rectangular piece of wood with height L and width W is free to rotate about its center. An upward force F acts at the upper right corner. What torque is exerted by this force around the center?

Basically Image is a Rectangle with a point in the center indicating pivot pt. Left side of rectangle denoted L and bottom is W.

Answer choices:

A.
FL / 2

B.
FW / 2

Correct Answer

C.

D.

Why isn't it C? What I did was c^2= a^2 + b^2. Then divided by 2 since we want the radius. I thought the force was being applied upward..


Answer is B. FW/2
Also if anyone has any tips on Pulleys/Tension.. I would really appreciate it! Thanks

 

[DrknoSDN]

I don't really know what the question was,,, but here is some potentially useful tips.

In torque problems you can imagine that the force vector is in a position that places it perpendicular to where an imaginary lever arm would be.
Thus because the force is pointing straight up the lever arm would be from the point of rotation to the center of right side of the block...

That would be Torque =1/2 width * Force.
Or Torque = F(W/2)

I'm going on a limb guessing it was asking, "What is an equation for torque?" or something like that.

 

[Iota]

I don't really know what the question was,,, but here is some potentially useful tips.

In torque problems you can imagine that the force vector is in a position that places it perpendicular to where an imaginary lever arm would be.
Thus because the force is pointing straight up the lever arm would be from the point of rotation to the center of right side of the block...

That would be Torque =1/2 width * Force.
Or Torque = F(W/2)

I'm going on a limb guessing it was asking, "What is an equation for torque?" or something like that.

Yeah sorry it seems i forgot to add that.. The question was: What torque is exerted by this force around the center?