Work Done by Torque on Square Plate of Mass M

AI Thread Summary
The discussion revolves around calculating the work done by a force F on a square plate of mass M that is fixed at the center and rotates due to the force applied perpendicularly. The attempt at a solution involves determining the moment arm and torque, with the torque expressed as FL/2. The challenge lies in finding the angle covered during rotation, as the book provides an answer involving time, which was not specified in the problem statement. The torque is noted to be constant, implying a constant angular acceleration, which can be expressed as a function of time. Clarification is sought on the relationship between angular acceleration and torque to further solve the problem.
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Homework Statement


In the figure shown a square plate of mass M and side of length L
is fixed at the center . The force F makes the square plate rotate.
The force is always perpendicular to the side.
Find the work done by the force.

Homework Equations


Work = torque x θ


The Attempt at a Solution


I considered the moment arm to be half of the diagonal of length L/√2
Then the force acting perpendicular to it will be F/√2
Torque =FL /2 but then how do i find the angle covered?
The book's answer is (3F2t2)/M
 

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1/2" said:

Homework Statement


In the figure shown a square plate of mass M and side of length L
is fixed at the center . The force F makes the square plate rotate.
The force is always perpendicular to the side.
Find the work done by the force.

Homework Equations


Work = torque x θ


The Attempt at a Solution


I considered the moment arm to be half of the diagonal of length L/√2
Then the force acting perpendicular to it will be F/√2
Torque =FL /2 but then how do i find the angle covered?
The book's answer is (3F2t2)/M

There is t in the solution but is not stated in the question.
 
The torque is constant, so the the angular acceleration is constant. So you can obtain it as a function of time.
 
voko said:
The torque is constant, so the the angular acceleration is constant. So you can obtain it as a function of time.

Can please be more elaborate ?
I reaaly appreciated your help,Thanks.:smile:
 
I am not sure what else I could say without solving the entire problem. What is the equation relating angular acceleration and torque?
 

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