Calculating Frictional Force: L, Lh, Lv, m

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To calculate the frictional force acting on a ladder, it's essential to analyze the forces and torques when the ladder is stationary. The key components include the horizontal and vertical forces, as well as the torques, which must all sum to zero. By establishing equations based on these components, one can derive the force F in terms of the lengths L, Lh, Lv, and the mass m. Additionally, the force exerted on the wall must also be considered in the calculations. Understanding these principles allows for determining the necessary coefficient of friction to prevent the ladder from slipping.
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Look at line a,assume it is not sliding down.Line b is sliding down,which means the frictional force of floor is smaller than F.
Line is of mass 1kg.Length is 2m, so C.M is in 1m
How do you find the force F interms of L,Lh, Lv,m each case?
L is the length of line. Lh is the horizontal distance. Lv is Vertical distance.
This is not a Home work Question or Homework type question .
I am just curious.
 

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You also need to consider the force on the wall.

If the ladder isn't moving (yet) then three things sum to zero..

The horizontal components of the forces
The vertical components of the forces
The torques.

By writing and solving these equations you can solve for the force F or work out the coefficient of friction required to stop the ladder slipping etc
 
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CWatters said:
You also need to consider the force on the wall.

If the ladder isn't moving (yet) then three things sum to zero..

The horizontal components of the forces
The vertical components of the forces
The torques.

By writing and solving these equations you can solve for the force F or work out the coefficient of friction required to stop the ladder slipping etc
Great Idea.Thanks.
 

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