Concept explainers
(a)
The tension in the wire.
Answer to Problem 77QAP
The tension in the wire is
Explanation of Solution
Given:
Mass of the beam
Let 'T' be the tension in the wire
Length of beam
Formula used:
Newton's 2nd law:
Torque (or moment of force)
Here, all alphabets are in their usual meanings.
Calculation: Pictorial Diagram
Consider the pictorial diagram wherein all components are shown
Apply Newton's 2nd law
For x − component:
For y − component:
Net Torque at the hinge
Therefore,
Hence, the tension in the wire is
Conclusion:
Thus, the tension in the wire is
(b)
The minimum cross-sectional area of the wire.
Answer to Problem 77QAP
The minimum cross-sectional area of the wire is
Explanation of Solution
Given:
Ultimate breaking strength
Let the minimum cross-sectional area of the wire be ' A'
Maximum applied force on the wire
Formula used:
Ultimate strength
Here, all alphabets are in their usual meanings.
Calculation:
Substituting the given values in above formula,
Hence, the minimum cross-sectional area of the wire is
Conclusion:
Thus, the minimum cross-sectional area of the wire is
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Chapter 9 Solutions
COLLEGE PHYSICS
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