Warning: foreach() argument must be of type array|object, bool given in /var/www/html/web/app/themes/studypress-core-theme/template-parts/header/mobile-offcanvas.php on line 20

Figure 6-53 shows a conical pendulum, in which the bob (the small object at the lower end of the cord) moves in a horizontal circle at constant speed. (The cord sweeps out a cone as the bob rotates.) The bob has a mass of 0.040 kg, the string has length L=0.90 mand negligible mass, and the bob follows a circular path of circumference 0.94 m. What are

(a) the tension in the string and

(b) the period of the motion?

Short Answer

Expert verified

a)T=0.4Nb)t=1.9s

Step by step solution

01

Given data

  • The circumference of the circular path “r” is 0.94 m .
  • The length of the cord “L” is 0.9 m .
  • The mass of bob “m” is 0.04 kg .
02

To understand the concept

The problem deals with Newton’s second law of motion, which states that the acceleration of an object is dependent upon the net force acting upon the object and the mass of the object.

Calculate the angle made by the cord.

Use Newton’s second law of motion to calculate the tension in the cord. After calculating the tension, calculate the velocity of the bob and the time required to complete one revolution.

03

(a) Calculate the tension in the string

The radius of the circular path R,

R=r2π=0.94m2π=0.15m

The angle cord makes with horizontal:

θ=cos-1R/L=cos-10.15m/0.94m=80°

To calculate tension, apply Newton’s second law of motion in a vertical direction:

Tsinθ=mg

Substitute the values in the above expression, and we get,

T=0.04kg×9.8m/s2sin80°=0.4N

Thus, the tension in the string is 0.4 N.

04

(b) Calculate the period of the motion

To calculate the velocity of bob, apply Newton’s second law of motion horizontal direction:

Tcosθ=mv2Rv=R×Tcosθm

Substitute the values in the above expression, and we get,

v=0.15m×0.4Ncos80°0.04kg=0.49m/s

To calculate the time to complete one revolution:

t=0.94m0.49m/s=1.9s

Thus, the period of motion is 1.9 s.

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 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

A baseball player with massm=79kg, sliding into second base, is retarded by a frictional force of magnitude470N.What is the coefficient of kinetic frictionμkbetween the player and the ground?

A sling-thrower puts a stone (0.250 kg). In the slings pouch (0.010 kg)and then begins to make the stone and pouch move in a vertical circle of radius 0.650 m. The cord between the pouch and the person’s hand has negligible mass and will break when the tension in the cord is 33.0 Nmore. Suppose the sling thrower could gradually increase the speed of the stone. (a) Will the breaking occur at the lowest point of the circle or at the highest point? (b) At what speed of the stone will that breaking occur?

A police officer in hot pursuit drives her car through a circular turn of radius 300mwith a constant speed of 80.0km/h. Her mass is55.0kg. What are (a) the magnitude and (b) the angle (relative to vertical) of the net force of the officer on the car seat? (Hint: Consider both horizontal and vertical forces)

Two blocks, of weights 3.6 Nand 7.2 N, are connectedby a massless string and slide down a30°inclined plane. The coefficient of kinetic friction between the lighter block and the plane is 0.10, and the coefficient between the heavier block and the plane is 0.20. Assuming that the lighter block leads, find (a) the magnitude of the acceleration of the blocks and (b) the tension in the taut string.

In Fig. 6-15, a horizontal force of 100Nis to be applied to a 10kg slab that is initially stationary on a frictionless floor, to accelerate the slab. A 10kg block lies on top of the slab; the coefficient of friction μbetween the block and the slab is not known, and the block might slip. In fact, the contact between the block and the slab might even be frictionless. (a) Considering that possibility, what is the possible range of values for the magnitude of the slab’s accelerationlocalid="1657173176346" aslab? (Hint:You don’t need written calculations; just consider extreme values for m.) (b) What is the possible range for the magnitudelocalid="1657173167508" ablockof the block’s acceleration?

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.

Sign-up for free