/*! 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 4 A bowling ball with a radius of ... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

A bowling ball with a radius of \(15.0 \mathrm{~cm}\) travels down the lane so that its center of mass is moving at \(3.60 \mathrm{~m} / \mathrm{s} .\) The bowler estimates that it makes about 7.50 complete revolutions in 2.00 seconds. Is it rolling without slipping? Prove your answer, assuming that the bowler's quick observation limits answers to two significant figures.

Short Answer

Expert verified
Yes, the ball is rolling without slipping as the calculated and given speeds are approximately equal.

Step by step solution

01

Calculate the Angular Speed of the Bowling Ball

First, we need to determine the angular speed \( \omega \) of the bowling ball. We know that the ball makes 7.50 revolutions in 2.00 seconds. Since 1 revolution is \( 2\pi \) radians, the total angle \( \theta \) covered is \( 7.50 \times 2\pi \) radians. The formula for angular speed is \( \omega = \frac{\theta}{t} \), where \( t \) is time. Thus, \( \omega = \frac{15\pi}{2} \approx 23.56 \, \text{rad/s}\).
02

Find Linear Speed Due to Rotation

The linear speed \( v \) due to rotation can be found using the formula \( v = r\omega \), where \( r \) is the radius of the ball, \( 0.15 \, \text{m} \). Substituting the values, we get \( v = 0.15 \times 23.56 \approx 3.53 \, \text{m/s}\).
03

Compare Actual Speed with Rolling Speed

We compare the calculated linear speed \( 3.53 \, \text{m/s} \) with the center of mass speed \( 3.60 \, \text{m/s} \) given in the problem. For the ball to roll without slipping, these speeds should be approximately equal.
04

Determine if the Ball is Rolling Without Slipping

Since the calculated linear speed due to rotation \( 3.53 \, \text{m/s} \) is very close to the actual center of mass speed \( 3.60 \, \text{m/s} \), and considering the precision allowed (two significant figures), we conclude that the ball is rolling without slipping.

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!

Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Angular Speed
Angular speed describes how quickly an object rotates or spins around its axis. In our bowling ball problem, angular speed is crucial to understanding the ball's rotation as it travels down the lane. Angular speed is usually denoted by the Greek letter \(\omega\) and is measured in radians per second (rad/s).
- **To calculate angular speed**, you first need to know how many rotations or revolutions an object makes. In this problem, the bowling ball completes 7.50 revolutions in 2.00 seconds.
- Each revolution of the ball corresponds to a complete circle, or \(2\pi\) radians.
- Thus, the total angle the ball covers is \(7.50 \times 2\pi\) radians.Using the formula for angular speed, \(\omega = \frac{\theta}{t}\), where \(\theta\) is the angle in radians and \(t\) is the time in seconds, we find \(\omega = \frac{15\pi}{2} \approx 23.56\, \text{rad/s}\). This calculation helps in understanding how fast the ball spins as it rolls.
Linear Speed
Linear speed is the rate at which an object moves along a path. It's crucial when analyzing rolling objects like our bowling ball.
- In essence, linear speed tells us how fast the center of mass of the ball travels down the lane.
- The linear speed due to rotation can be linked to the angular speed using the equation \(v = r\omega\), where \(r\) is the radius of the ball and \(\omega\) is the angular speed calculated earlier.
Knowing the radius of the ball is 0.15 meters, we can calculate:
\[v = 0.15 \times 23.56 \approx 3.53\, \text{m/s}\]This linear speed due to rotation needs to closely match the actual linear speed of the ball's center of mass, calculated as 3.60 m/s, to check if it rolls without slipping.
Rolling Without Slipping
When an object rolls without slipping, there is no relative motion between the point of contact and the surface. In simpler terms, the ball spins just right to match its movement down the lane.
- For rolling without slipping, the linear speed of the outer surface due to rotation must be equal to the speed of the ball's center of mass.
- In our bowling ball example, the calculated linear speed due to rotation was 3.53 m/s, closely matching the observed center of mass speed of 3.60 m/s.
Given the small difference and the consideration of two significant figures (which accounts for minor discrepancies), we conclude that the bowling ball is indeed rolling without slipping. This concept ensures that the ball rotates correctly relative to its motion, providing a smooth path with no skidding along the lane.

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

In a tumbling clothes dryer, the cylindrical drum (radius \(50.0 \mathrm{~cm}\) and mass \(35.0 \mathrm{~kg}\) ) rotates once every second. (a) Determine the rotational kinetic energy about its central axis. (b) If it started from rest and reached that speed in \(2.50 \mathrm{~s}\), determine the average net torque on the dryer drum.

A cylindrical hoop, a cylinder, and a sphere of equal radius and mass are released at the same time from the top of an inclined plane. Using the conservation of mechanical energy, show that the sphere always gets to the bottom of the incline first with the fastest speed and that the hoop always arrives last with the slowest speed.

Telephone and electrical lines are allowed to sag between poles so that the tension will not be too great when something hits or sits on the line. (a) Is it possible to have the lines perfectly horizontal? Why or why not? (b) Suppose that a line were stretched almost perfectly horizontally between two poles that are \(30 \mathrm{~m}\) apart. If a \(0.25-\mathrm{kg}\) bird perches on the wire midway between the poles and the wire sags \(1.0 \mathrm{~cm},\) what would be the tension in the wire? (Neglect the mass of the wire.)

A steel ball rolls down an incline into a loop-theloop of radius \(R\) (v Fig. 8.52a). (a) What minimum speed must the ball have at the top of the loop in order to stay on the track? (b) At what vertical height \((h)\) on the incline, in terms of the radius of the loop, must the ball be released in order for it to have the required minimum speed at the top of the loop? (Neglect frictional losses.) (c) Figure \(8.52 \mathrm{~b}\) shows the loop-the-loop of a roller coaster. What are the sensations of the riders if the roller coaster has the minimum speed or a greater speed at the top of the loop? [Hint: In case the speed is below the minimum, seat and shoulder straps hold the riders in.

A planetary space probe is in the shape of a cylinder. To protect it from heat on one side (from the Sun's rays), operators on the Earth put it into a "barbecue mode," that is, they set it rotating about its long axis. To do this, they fire four small rockets mounted tangentially as shown in \(v\) Fig. 8.51 (the probe is shown coming toward you). The object is to get the probe to rotate completely once every \(30 \mathrm{~s}\), starting from no rotation at all. They wish to do this by firing all four rockets for a certain length of time. Each rocket can exert a thrust of \(50.0 \mathrm{~N}\). Assume the probe is a uniform solid cylinder with a radius of \(2.50 \mathrm{~m}\) and a mass of \(1000 \mathrm{~kg}\) and neglect the mass of each rocket engine. Determine the amount of time the rockets need to be fired.

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.