/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 80 A crow perches on a clothesline ... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

A crow perches on a clothesline midway between two poles. Each end of the rope makes an angle of \(\theta\) below the horizontal where it connects to the pole. If the weight of the crow is \(W,\) what is the tension in the rope? Ignore the weight of the rope.

Short Answer

Expert verified
Answer: \(T = \frac{W}{2 \sin(\theta)}\)

Step by step solution

01

Draw a free body diagram of the situation

To better visualize the forces acting on the situation, let's draw a free body diagram of the rope, crow, and tension forces from each pole. Two tension forces, T1 and T2, act at each end of the rope making an angle of \(\theta\) below the horizontal, and the weight of the crow W acts downwards in the middle.
02

Write down the vertical and horizontal force equilibrium equations

Using equilibrium conditions, we can write the vertical and horizontal force equations: Vertical forces: \(T1 \sin(\theta) + T2 \sin(\theta) - W = 0\) (1) Horizontal forces: \(T1 \cos(\theta) - T2 \cos(\theta) = 0\) (2)
03

Solve the horizontal force equation for T1 or T2

Since \(T1 \cos(\theta) = T2 \cos(\theta)\), we can divide both sides of the equation by \(\cos(\theta)\) to find: \(T1 = T2\)
04

Substitute T1 into the vertical force equation

Now we can substitute \(T2\) for \(T1\) in the vertical force equation (1) to get: \(2T2 \sin(\theta) - W = 0\)
05

Solve for T2 (or T1)

Rearranging the equation and solving for \(T2\), we get: \(T2 = \frac{W}{2 \sin(\theta)}\)
06

Calculate the tension T in the rope

Since \(T1 = T2\), we can conclude that the tension T in the rope is: \(T = \frac{W}{2 \sin(\theta)}\) Now, we have found the tension T in the rope as a function of the weight of the crow W and the angle \(\theta\).

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

At what altitude above the Earth's surface would your weight be half of what it is at the Earth's surface?
Refer to Problem \(36 .\) Consider the skydiver and parachute to be a single system. What are the external forces acting on this system?
An airplane is cruising along in a horizontal level flight at a constant velocity, heading due west. (a) If the weight of the plane is $2.6 \times 10^{4} \mathrm{N},$ what is the net force on the plane? (b) With what force does the air push upward on the plane?
A large wooden crate is pushed along a smooth, frictionless surface by a force of \(100 \mathrm{N}\). The acceleration of the crate is measured to be $2.5 \mathrm{m} / \mathrm{s}^{2} .$ What is the mass of the crate?
In Fig. 4.15 an astronaut is playing shuffleboard on Earth. The puck has a mass of \(2.0 \mathrm{kg} .\) Between the board and puck the coefficient of static friction is 0.35 and of kinetic friction is \(0.25 .\) (a) If she pushes the puck with a force of \(5.0 \mathrm{N}\) in the forward direction, does the puck move? (b) As she is pushing, she trips and the force in the forward direction suddenly becomes \(7.5 \mathrm{N} .\) Does the puck move? (c) If so, what is the acceleration of the puck along the board if she maintains contact between puck and stick as she regains her footing while pushing steadily with a force of \(6.0 \mathrm{N}\) on the puck? (d) She carries her game to the Moon and again pushes a moving puck with a force of \(6.0 \mathrm{N}\) forward. Is the acceleration of the puck during contact more, the same, or less than on Earth? Explain. (tutorial: rough table)
See all solutions

Recommended explanations on Physics Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.