Concept explainers
(a)
The horizontal and vertical forces the ground exerts on the base of the ladder.
(a)
Answer to Problem 13P
The forces in the horizontal direction are, normal force exerts by the wall is
Explanation of Solution
Write the first condition for equilibrium, the magnitude of the net external force on the object must be equal zero:
Here,
Write the second condition for equilibrium, the magnitude of net external torque on the object about a fixpoint must be zero:
Here,
The forces acting on the ladder are shown as.
Write the first equilibrium condition for the ladder in
Here,
Write the first equilibrium condition for the ladder in
Here,
Write the expression for the weight of the body.
Here,
If the mass is
Write the expression for second equilibrium for the ladder in as
Here,
Substitute
Here,
Simplify the above expression for
Re-arrange the terms.
Substitute
Re-arrange the terms.
Conclusion:
Substitute
Substitute
Simplify the above expression for
Substitute
Simplify the above expression for
Thus, the forces in horizontal direction are, normal force exerts by the wall is
(b)
The coefficient of static friction at the verge of sliding between ladder and ground.
(b)
Answer to Problem 13P
The coefficient of static friction at the verge of sliding between ladder and ground is
Explanation of Solution
At the verge of slipping the
Here,
At the verge of slipping, substitute
Here,
Conclusion:
Substitute
Re-arrange the terms,
Substitute
Thus, the coefficient of static friction at the verge of sliding between ladder and ground is
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Chapter 12 Solutions
Physics: for Science.. With Modern. -Update (Looseleaf)
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