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Ch 11: Equilibrium & Elasticity
Young & Freedman Calc - University Physics 14th Edition
Young & Freedman Calc14th EditionUniversity PhysicsISBN: 9780321973610당신이 사용하는 게 아니라요?교과서 변경
11장, 문제 13b

Find the tension T in each cable and the magnitude and direction of the force exerted on the strut by the pivot in each of the arrangements in Fig. E11.13. In each case let w be the weight of the suspended crate full of priceless art objects. The strut is uniform and also has weight w. Start each case with a free-body diagram of the strut.

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1
Begin by drawing a free-body diagram for the strut in arrangement (b). Identify all forces acting on the strut: the tension T in the cable, the weight of the strut (w), the weight of the crate (w), and the reaction forces at the pivot (horizontal and vertical components).
Apply the equilibrium condition for torques about the pivot point. Choose the pivot as the point of rotation to eliminate the reaction forces from the torque equation. Set the sum of the torques equal to zero. Consider the perpendicular distances from the pivot to the line of action of each force.
Write the torque equation: \( T \cdot L \cdot \sin(45^\circ) - w \cdot \frac{L}{2} \cdot \cos(30^\circ) - w \cdot L \cdot \cos(30^\circ) = 0 \), where L is the length of the strut. Solve this equation for the tension T.
Apply the equilibrium conditions for forces in the horizontal and vertical directions. For horizontal forces: \( T \cdot \cos(45^\circ) = F_{horizontal} \). For vertical forces: \( T \cdot \sin(45^\circ) + F_{vertical} = 2w \).
Solve the system of equations obtained from the force equilibrium conditions to find the horizontal and vertical components of the force exerted by the pivot. Use these components to determine the magnitude and direction of the force exerted by the pivot.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.
영상 길이:
17m
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주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Free-Body Diagram

A free-body diagram is a graphical representation used to visualize the forces acting on an object. In this context, it helps identify all forces acting on the strut, including tension in the cables, gravitational forces due to the weights of the crate and the strut, and any reaction forces at the pivot. This diagram is essential for applying Newton's laws to solve for unknown forces.
추천 영상:
가이드 코스
08:42
Free-Body Diagrams

Tension in Cables

Tension is the force exerted along a cable or rope when it is pulled tight by forces acting from opposite ends. In this scenario, the tension in the cables must balance the weight of the suspended crate and the strut. Understanding how to calculate tension involves analyzing the angles and applying trigonometric functions to resolve forces into their components.
추천 영상:
가이드 코스
03:25
Multiple Cables on a Loudspeaker

Equilibrium of Forces

The concept of equilibrium states that an object at rest has a net force of zero acting on it. For the strut in this problem, this means that the sum of all vertical and horizontal forces must equal zero. This principle is crucial for determining the magnitudes and directions of the forces exerted on the strut by the pivot and the tension in the cables.
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