Log out Go to App
Go to App

Learning Materials

Features

Discover

Chapter 9: Q4MCQ (page 230)

A heavy ball suspended by a cable is pulled to the side by a horizontal force \(\vec F\), as shown in Fig. 9–43. If angle \(\theta \) is small, the magnitude of the force F can be less than the weight of the ball because

(a) the force holds up only part of the ball’s weight.

(b) even though the ball is stationary, it is not really in equilibrium.

(c) \(\vec F\) is equal to only the x component of the tension in the cable.

(d) the original statement is not true. To move the ball, \(\vec F\) must be at least equal to the ball’s weight.

Short Answer

Expert verified

The correct option is (c).

Step by step solution

01

Concepts

At equilibrium, the net force is zero.For this problem, the horizontal and vertical forces balance each other for the equilibrium of the ball.

02

Explanation

Let m be the mass of the ball and T be the tension in the cable. The cable makes \(\theta \) angle with the vertical.

Condition for equilibrium:

For the horizontal forces, the magnitude of the force is equal to the x component of the tension force.

For the vertical force, the weight is equal to the y component of the tension force.

Hence, option (c) is correct.

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.

Start your free trial

Over 30 million students worldwide already upgrade their learning with Vaia!

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

(II) A 110-kg horizontal beam is supported at each end. A 320-kg piano rests a quarter of the way from one end. What is the vertical force on each of the supports?

A parking garage is designed for two levels of cars. To make more money, the owner decides to double the size of the garage in each dimension (length, width, and the number of levels). For the support columns to hold up four floors instead of two, how should he change the columns' diameter?

(a) Double the area of the columns by increasing their diameters by a factor of 2

(b) Double the area of the columns by increasing their diameters by a factor of \(\sqrt 2 \)

(c) Quadruple the area of the columns by increasing their diameters by a factor of 2

(d) Increase the area of the columns by a factor of 8 by increasing their diameters by a factor of \(2\sqrt 2 \)

(e) He doesn't need to increase the diameter of the columns

(I) By how much is the column in Problem 41 shortened if it is 8.6 m high?

Three children are trying to balance on a seesaw, which includes a fulcrum rock acting as a pivot at the center and a very light board that is 3.2 m long (Fig. 9–57). Two playmates are already on either end. Boy A has a mass of 45 kg, and boy B has a mass of 35 kg. Where should girl C, whose mass is 25 kg, place herself to balance the seesaw?

(I) Suppose the point of insertion of the biceps muscle into the lower arm shown in Fig. 9–13a (Example 9–8) is 6.0 cm instead of 5.0 cm; how much mass could the person hold with a muscle exertion of 450 N?
See all solutions

Recommended explanations on Physics Textbooks

Mechanics and Materials

Read Explanation

Electric Charge Field and Potential

Read Explanation

Medical Physics

Read Explanation

Particle Model of Matter

Read Explanation

Geometrical and Physical Optics

Read Explanation

Solid State Physics

Read Explanation
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.

Sign-up for free