What Minimum Force is Needed to Lift a Wheel Over an Obstacle?

AI Thread Summary
The discussion focuses on determining the minimum horizontal force required to lift a wheel over an obstacle of height h, considering the wheel's radius r and weight W. Participants explore the relationship between torque, angular acceleration, and the forces acting on the wheel. The torque equation T = rFnet is central to the analysis, leading to discussions about calculating angular acceleration and incorporating the height of the obstacle. A key point is to ensure the torque about the contact point between the wheel and the obstacle is zero, balancing the weight and the applied force. Visual aids, such as drawings, are suggested to clarify the problem setup.
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What minimum force F applied horizontally at the axle of the wheel is necessary to raise the wheel over an obstacle of height h? Take r as the radius of the wheel and W as its weight.

We know torque is equal to the radius x perpendicular force
T = rFnet

I think I have to find angular acceleration, α.

T = rma
T = rmα
T = rm(αr)
T = α(mr^2)
ΣT = αΣ(mr^2)

am I on the right track so far?
How do I incorporate height into this, do I want to find angular acceleration in the y direction?
 
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Do they give a picture? If not draw a picture... Draw a wheel standing against a block of height h.

the point where the block and the wheel touch... you want the torque about the point to be zero...

you have two forces involved for this torque... the weight and the horizontal applied force.
 
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