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Question
A body of mass M is kept on a rough horizontal surface (friction coefficient = μ). A person is trying to pull the body by applying a horizontal force but the body is not moving. The force by the surface on A is F, where
Options
F = Mg
F = μ Mg
Mg ≤ F ≤ Mga `sqrt(1+mu^2)`
Mg ≥ F ≥ Mg `sqrt(1-mu^2)`
Solution
Mg ≤ F ≤ Mga `sqrt(1+mu^2)`
Let T be the force applied on an object of mass M.
If T = 0, Fmin = Mg.
If T is acting in the horizontal direction, then the body is not moving.
∴ T = μ(mg)
Fmax = `sqrt("Mg"^2+"T"^2)`
= `sqrt("Mg"^2+(mu"Mg")^2)`
Thus, we have:
Mg ≤ F ≤ Mga `sqrt(1+mu^2)`
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