Concept explainers
(a)
The fraction of weight supported by the opposite shore.
Answer to Problem 12PE
The fraction of weight supported by the opposite shore is
Explanation of Solution
Given:
The mass of the bridge is,
Formula used:
The relation between the mass and weight is,
The expression for condition of equilibrium is,
The relation between the fraction of weight and tension is,
The free body diagram for the bridge is shown below.
Figure-(1)
Calculation:
The weight of the bridge is calculated as,
The tension is calculated as,
Solve further:
The fraction of weight is calculated as,
Conclusion:
The fraction of weight supported by the opposite shore is
(b)
The direction and magnitude of the force exerted on the bridge.
Answer to Problem 12PE
The magnitude of the force is
Explanation of Solution
Given:
The mass of the bridge is
Formula used:
The expression for condition of equilibrium is,
The expression for force along horizontal is,
Calculation:
The vertical component of the force is calculated as,
The horizontal component of the force is calculated as,
The magnitude of the force is given as,
The direction of the force is given as,
Conclusion:
The magnitude of the force is
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Chapter 9 Solutions
COLLEGE PHYSICS
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