College Physics: A Strategic Approach (3rd Edition)
3rd Edition
ISBN: 9780321879721
Author: Randall D. Knight (Professor Emeritus), Brian Jones, Stuart Field
Publisher: PEARSON
expand_more
expand_more
format_list_bulleted
Concept explainers
Textbook Question
Chapter 6, Problem 19P
A baseball pitching machine works by rotating a light and stiff rigid rod about a horizontal axis until the ball is moving toward the target. Suppose a 144 g baseball is held 85 cm from the axis of rotation and released at the major league pitching speed of 85 mph.
a. What is the ball’s centripetal acceleration just before it is released?
b. What is the magnitude of the net force that is acting on the ball just before it is released?
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
A racecar is driven on a horizontal circular track at a constant speed of 20.0 m/s. The radius of the track is 100.0 meters and the mass of the car is 800.0 kg.
a. Does the racecar accelerate and if it does in what direction is the acceleration? EXPLAIN!
b. What is the centripetal force on the racecar?
c. What is the value of the static frictional force between the tires and the track?
d. Explain what (and why) the driver of the racecar should do if it started to rain in order to keep driving in a circle. Make sure to explain what happens to the frictional force when it begins to rain and make sure to explain how the driver’s action changes the centripetal force on the racecar.
A conical pendulum is formed by attaching a ball of mass m to a string of length L, then allowing the ball to move in a horizontal circle of radius r.
a. Draw a free-body diagram for the ball. b.
Find an expression for the tension Tin the string in terms of m and 0.
C. Find an expression for the ball's angular speed w in terms of r and 0.
D. What are the tension and angular speed (in rpm) for a 500 g ball swinging in a 20-cm-radius circle at the end of a 1.0-m-long string?
Point
A flat (unbanked) curve on a highway has a radius of 182.5 m. A car rounds the curve at a speed
of 35.0 m/s.
a. What is the minimum coefficient of static friction that will prevent sliding?
b. Suppose that the highway is icy and the coefficient of static friction between the tires
and pavement is only one-third of what you found in part (a). What should be the
maximum speed of the car so that it can round the curve safely?
Chapter 6 Solutions
College Physics: A Strategic Approach (3rd Edition)
Ch. 6 - A cyclist goes around a level, circular track at...Ch. 6 - In uniform circular motion, which of the following...Ch. 6 - A particle moving along a straight line can have...Ch. 6 - Would having four-wheel drive on a car make it...Ch. 6 - Large birds like pheasants often walk short...Ch. 6 - When you drive fast on the highway with muddy...Ch. 6 - A ball on a string moves in a vertical circle as...Ch. 6 - Give an everyday example of circular motion for...Ch. 6 - Give an everyday example of circular motion for...Ch. 6 - Its been proposed that future space stations...
Ch. 6 - A car coasts at a constant speed over a circular...Ch. 6 - In Figure Q6.11, at the instant shown, is the...Ch. 6 - Riding in the back of a pickup truck can be very...Ch. 6 - Playground swings move through an arc of a circle....Ch. 6 - Variation in your apparent weight is desirable...Ch. 6 - A small projectile is launched parallel to the...Ch. 6 - Why is it impossible for an astronaut inside an...Ch. 6 - If every object in the universe feels an...Ch. 6 - A mountain climbers weight is slightly less on the...Ch. 6 - Is the earths gravitational force on the sun...Ch. 6 - A ball on a string moves around a complete circle,...Ch. 6 - As seen from above, a car rounds the curved path...Ch. 6 - As we saw in the chapter, wings on race cars push...Ch. 6 - Suppose you and a friend, each of mass 60 kg, go...Ch. 6 - The cylindrical space station in Figure Q6.25, 200...Ch. 6 - Two cylindrical space stations, the second four...Ch. 6 - The radius of Jupiter is 11 times that of earth,...Ch. 6 - A newly discovered planet has twice the mass and...Ch. 6 - Suppose one night the radius of the earth doubled...Ch. 6 - Currently, the moon goes around the earth once...Ch. 6 - Two planets orbit a star. You can ignore the...Ch. 6 - A 5.0-m-diameter merry-go-round is turning with a...Ch. 6 - The blade on a table saw spins at 3450 rpm. Its...Ch. 6 - An old-fashioned LP record rotates at 3313rpm. a....Ch. 6 - A typical hard disk in a computer spins at 5400...Ch. 6 - A CD-ROM drive in a computer spins the...Ch. 6 - The horse on a carousel is 4.0 m from the central...Ch. 6 - The radius of the earths very nearly circular...Ch. 6 - Modern wind turbines are larger than they appear,...Ch. 6 - Your roommate is working on his bicycle and has...Ch. 6 - Wind turbines designed for offshore installations...Ch. 6 - To withstand g-forces of up to 10g, caused by...Ch. 6 - A typical running track is an oval with...Ch. 6 - Figure P6.13 is a birds-eye view of particles on a...Ch. 6 - In short-track speed skating, the track has...Ch. 6 - A 200 g block on a 50-cm-long string swings in a...Ch. 6 - A cyclist is rounding a 20-m-radius curve at 12...Ch. 6 - A 1500 kg car drives around a flat 200-m-diameter...Ch. 6 - A fast pitch softball player does a windmill...Ch. 6 - A baseball pitching machine works by rotating a...Ch. 6 - A wind turbine has 12,000 kg blades that are 38 m...Ch. 6 - Youre driving your pickup truck around a curve...Ch. 6 - You have seen dogs shake to shed water from their...Ch. 6 - Gibbons, small Asian apes, move by brachiation,...Ch. 6 - The passengers in a roller coaster car feel 50%...Ch. 6 - You hold a bucket in one hand. In the bucket is a...Ch. 6 - A roller coaster car is going over the top of a...Ch. 6 - As a roller coaster car crosses the top of a...Ch. 6 - An 80-ft-diameter Ferris wheel rotates once every...Ch. 6 - A typical laboratory centrifuge rotates at 4000...Ch. 6 - A satellite orbiting the moon very near the...Ch. 6 - Spacecraft have been sent to Mars in recent years....Ch. 6 - The centers of a 10 kg lead ball and a 100 g lead...Ch. 6 - The gravitational force of a star on an orbiting...Ch. 6 - The free-fall acceleration at the surface of...Ch. 6 - What is the ratio of the suns gravitational force...Ch. 6 - Suppose the free-fall acceleration at some...Ch. 6 - In recent years, astronomers have found planets...Ch. 6 - In recent years, astronomers have found planets...Ch. 6 - a. What is the gravitational force of the sun on...Ch. 6 - What is the value of g on the surface of Saturn?...Ch. 6 - What is the free-fall acceleration at the surface...Ch. 6 - Planet X orbits the star Omega with a year that is...Ch. 6 - Prob. 43PCh. 6 - The International Space Station is in a...Ch. 6 - The asteroid belt circles the sun between the...Ch. 6 - An earth satellite moves in a circular orbit at a...Ch. 6 - In recent years, scientists have discovered...Ch. 6 - In recent years, scientists have discovered...Ch. 6 - In recent years, scientists have discovered...Ch. 6 - How fast must a plane fly along the earths equator...Ch. 6 - The car in Figure P6.51 travels at a constant...Ch. 6 - In the Bohr model of the hydrogen atom, an...Ch. 6 - A 75 kg man weighs himself at the north pole and...Ch. 6 - A 1500 kg car takes a 50-m-radius unbanked curve...Ch. 6 - A 500 g ball swings in a vertical circle at the...Ch. 6 - A 5.0 g coin is placed 15 cm from the center of a...Ch. 6 - A conical pendulum is formed by attaching a 500 g...Ch. 6 - In an old-fashioned amusement park ride,...Ch. 6 - The 0.20 kg puck on the frictionless, horizontal...Ch. 6 - While at the county fair, you decide to ride the...Ch. 6 - A car drives over the top of a hill that has a...Ch. 6 - A 100 g ball on a 60-cm-long string is swung in a...Ch. 6 - Prob. 63GPCh. 6 - The ultracentrifuge is an important tool for...Ch. 6 - A sensitive gravimeter at a mountain observatory...Ch. 6 - Suppose we could shrink the earth without changing...Ch. 6 - Planet Z is 10,000 km in diameter. The free-fall...Ch. 6 - Prob. 68GPCh. 6 - Prob. 69GPCh. 6 - How long will it take a rock dropped from 2.0 m...Ch. 6 - A 20 kg sphere is at the origin and a 10 kg sphere...Ch. 6 - a. At what height above the earth is the free-fall...Ch. 6 - Mars has a small moon, Phobos, that orbits with a...Ch. 6 - You are the science officer on a visit to a...Ch. 6 - Europa, a satellite of Jupiter, is believed to...Ch. 6 - The direction of the net force on the craft is A....Ch. 6 - Suppose a spacecraft orbits the moon in a very...Ch. 6 - How much time does it take for the spacecraft to...Ch. 6 - The material that comprises the side of the moon...
Additional Science Textbook Solutions
Find more solutions based on key concepts
At the right is a sketch showing one of the atoms in the diffuse, cool cloud of gas described in the previous q...
Lecture- Tutorials for Introductory Astronomy
A 45-kg skater rounds a 5.0-m-radius turn at 6.3 m/s. (a) What are the horizontal and vertical components of th...
Essential University Physics: Volume 1 (3rd Edition)
Explain all answers clearly, with complete sentences and proper essay structure if needed. An asterisk (*) desi...
Cosmic Perspective Fundamentals
(a) An exterior wall of a house is 3 m tall and 10 m wide. It consists of a layer of drywall with an R factor o...
University Physics Volume 2
The term decelerate is often used to indicate that an object is slowing down. Does this term indicate the sign ...
Tutorials in Introductory Physics
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, physics and related others by exploring similar questions and additional content below.Similar questions
- (a) What is the acceleration due to gravity on the surface of the Moon? (b) On the surface of Mars? The mass of Mars is 6.4181023 kg and its radius is 3.38106 m.arrow_forwardThree billiard balls, the two-ball, the four-ball, and the eight-ball, are arranged on a pool table as shown in Figure P7.26. Given the coordinate system shown and that the mass of each ball is 0.150 kg, determine the gravitational field at x=2m, y=0.arrow_forwardBanked curves are designed so that the radial component of the normal force on the car rounding the curve provides the centripetal force required to execute uniform circular motion and safely negotiate the curve. A car rounds a banked curve with banking angle = 22.0 and radius of curvature 150 m. a. If the coefficient of static friction between the cars tires and the road is s = 0.400, what is the range of speeds for which the car can safely negotiate the turn without slipping? b. What is the minimum value of s for which the cars minimum safe speed is zero? Note that friction points up the incline here.arrow_forward
- A 0.275-kg object is swung in a vertical circular path on a string 0.850 m long as in Figure P7.70. (a) What are the forces acting on the ball at any point along this path? (b) Draw free-body diagrams for the ball when it is at the bottom of the circle and when it is at the top. (c) If its speed is 5.20 m/s at the top of the circle, what is the tension in the string there? (d) If the string breaks when its tension exceeds 22.5 N, what is the maximum speed the object can have at the bottom before the string breaks? Figure P7.70arrow_forward(a) Suppose that your measured weight at the equator is one-half your measured weight at the pole on a planet whose mass and diameter are equal to those of Earth. What is the rotational period of the planet? (b) Would you need to take the shape of this planet into account?arrow_forwardPlanetary orbits are often approximated as uniform circular motion. Figure P7.9 is a scaled representation of a planets orbit with a semimajor axis of 1.524 AU. a. Use Figure P7.9 to find the ratio of the Suns maximum gravitational field to its minimum gravitational field on the planets orbit. b. What is the ratio of the planets maximum speed to its minimum speed? c. Comment on the validity of approximating this orbit as uniform circular motion.arrow_forward
- The pilot of an airplane executes a loop-the-loop maneuver in a vertical circle. The speed of the airplane is 300 mi/h at the top of the loop and 450 mi/h at the bottom, and the radius of the circle is 1 200 ft. (a) What is the pilots apparent weight at the lowest point if his true weight is 160 lb? (b) What is his apparent weight at the highest point? (c) What If? Describe how the pilot could experience weightlessness if both the radius and the speed can be varied. Note: His apparent weight is equal to the magnitude of the force exerted by the seat on his body.arrow_forwardSince March 2006, NASAs Mars Reconnaissance Orbiter (MRO) has been in a circular orbit at an altitude of 316 km around Mars (Fig. P6.81). The acceleration due to gravity on the surface of the planet Mars is 0.376g, and its radius is 3.40 103 km. Assume the acceleration due to gravity at the satellite is the same as on the planets surface. a. What is MROs orbital speed? B. What is the period of the spacecrafts orbit? FIGURE P6.81arrow_forwardA couple of astronauts agree to rendezvous in space after hours. Their plan is to let gravity bring them together. One of them has a mass of 65.0 kg and the other a mass of 72.0 kg and they start from rest 20.0 m apart. a. Draw a free-body diagram of each astronaut, and use it to find his or her initial acceleration. As a rough approximation, we can model the astronauts as uniform spheres. b. If the astronauts' acceleration remained constant, how many days would they have to wait before reaching each other? Careful! They both have acceleration toward each other! c. Would their acceleration, in fact, remain constant? If not, would it increase or decrease? Why?arrow_forward
- A body of mass 2 kg moves in a (counterclockwise) circular path of radius 10 meters, making one revolution every 7 seconds. You may assume the circle is in the xy-plane, and so you may ignore the third component. A. Compute the centripetal force acting on the body. B. Compute the magnitude of that force. Note: Use exact forms or at least 4 significant digits in your answers.arrow_forwardE8. A Ferris wheel at a carnival has a radius of 10 m and turns so that the speed of the riders is 8 m/s. a. What is the magnitude of the centripetal acceleration of the riders?b. What is the magnitude of the net force required to produce this centripetal acceleration for a rider with a mass of 60 kg?arrow_forwardA child ties a 0.3 kg stone to one end of a string. Holding the other end, the child whirls the stone in a vertical circle of radius 0.9 m. a. At the top of the circle, the speed of the stone is 8 m/s. What is the tension in the string? Draw the free body diagram. b. At the bottom of the circle, the speed of the stone is 9 m/s. What is the tension in the string? Draw the free body diagram. c. The string can withstand a maximum tension of 40 N before it breaks. The child whirls the stone faster and faster. At what point on the circle does the string break? Show this point on a circle, then draw the trajectory of the stone after breaking. Make sure you clearly show the direction of the stone immediately after the string breaks. d. What is the speed of the stone as the string breaks?arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Physics for Scientists and Engineers with Modern ...PhysicsISBN:9781337553292Author:Raymond A. Serway, John W. JewettPublisher:Cengage LearningPhysics for Scientists and Engineers: Foundations...PhysicsISBN:9781133939146Author:Katz, Debora M.Publisher:Cengage LearningCollege PhysicsPhysicsISBN:9781305952300Author:Raymond A. Serway, Chris VuillePublisher:Cengage Learning
- College PhysicsPhysicsISBN:9781285737027Author:Raymond A. Serway, Chris VuillePublisher:Cengage LearningUniversity Physics Volume 1PhysicsISBN:9781938168277Author:William Moebs, Samuel J. Ling, Jeff SannyPublisher:OpenStax - Rice UniversityPrinciples of Physics: A Calculus-Based TextPhysicsISBN:9781133104261Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning
Physics for Scientists and Engineers with Modern ...
Physics
ISBN:9781337553292
Author:Raymond A. Serway, John W. Jewett
Publisher:Cengage Learning
Physics for Scientists and Engineers: Foundations...
Physics
ISBN:9781133939146
Author:Katz, Debora M.
Publisher:Cengage Learning
College Physics
Physics
ISBN:9781305952300
Author:Raymond A. Serway, Chris Vuille
Publisher:Cengage Learning
College Physics
Physics
ISBN:9781285737027
Author:Raymond A. Serway, Chris Vuille
Publisher:Cengage Learning
University Physics Volume 1
Physics
ISBN:9781938168277
Author:William Moebs, Samuel J. Ling, Jeff Sanny
Publisher:OpenStax - Rice University
Principles of Physics: A Calculus-Based Text
Physics
ISBN:9781133104261
Author:Raymond A. Serway, John W. Jewett
Publisher:Cengage Learning
What Is Circular Motion? | Physics in Motion; Author: GPB Education;https://www.youtube.com/watch?v=1cL6pHmbQ2c;License: Standard YouTube License, CC-BY