Essential University Physics (3rd Edition)
3rd Edition
ISBN: 9780134202709
Author: Richard Wolfson
Publisher: PEARSON
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Textbook Question
Chapter 10, Problem 77P
You’re skeptical about a new hybrid car that stores energy in a flywheel. The manufacturer claims the flywheel stores 12 MJ of energy and can supply 40 kW of power for 5 minutes. You dig deeper and find that the flywheel is a 39-cm-diameter ring with mass 48 kg that rotates at 30.000 rpm. Are the specs correct?
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You go to the gym to ride a stationary bicycle. The bicycle uses a large wheel to create resistance for yourexercise. The wheel consists of some small spokes (we’ll ignore the spokes) and a hollow cylinder with aninner radius of 12cm, an outer radius of 35cm, and a mass of 48.9kg.You start with the bike not moving and peddle at a constant acceleration for 10sec to accelerate the wheelup to 36rads .3) What was the angular acceleration? 4) How much torque did you apply to the wheel?With the bike’s wheel spinning at 36rads you decide to turn up the resistance to get a good workout.5) If the bike is operated at a power level of 250W of resistance for 30 minutes, how much work will youhave done? 6) How much torque did you need to apply to the wheel to accomplish that workout?
Chapter 10 Solutions
Essential University Physics (3rd Edition)
Ch. 10.1 - A wheel undergoes constant angular acceleration,...Ch. 10.2 - The forces in Figs. 10.5 and 10.6 all have the...Ch. 10.3 - Would the rotational inertia of the two-mass...Ch. 10.3 - Explain why the rotational inertia of the solid...Ch. 10.3 - The figure shows two identical masses m connected...Ch. 10.4 - A wheel is rotating at 100 rpm. To spin it up to...Ch. 10.5 - The wheels of trains, subway cars, and other rail...Ch. 10 - Do all points on a rigid, rotating object have the...Ch. 10 - Prob. 2FTDCh. 10 - Why doesnt it make sense to talk about a bodys...
Ch. 10 - Two forces act on an object, but the net force is...Ch. 10 - Is it possible to apply a counterclockwise torque...Ch. 10 - A solid sphere and a hollow sphere of the same...Ch. 10 - A solid cylinder and a hollow cylinder of the same...Ch. 10 - A circular saw lakes a long time to stop rotating...Ch. 10 - A solid sphere and a solid cube have the same...Ch. 10 - The lower part of a horses leg contains...Ch. 10 - Given a fixed amount of a material, what shape...Ch. 10 - A ball starts from rest and rolls without slipping...Ch. 10 - Exercises and Problems Exercises Section 10.1...Ch. 10 - Whats the linear speed of a point (a) on Earths...Ch. 10 - Express each of the following in radians per...Ch. 10 - A 25-cm-diameter circular saw blade spins at 3500...Ch. 10 - A compact discs rotation varies from about 200 rpm...Ch. 10 - During startup, a power plants turbine accelerates...Ch. 10 - A merry-go-round starts front rest and accelerates...Ch. 10 - Section 10.2 Torque A 320-N frictional force acts...Ch. 10 - A 110-N m torque is needed to start a revolving...Ch. 10 - A car tune-up manual calls for tightening the...Ch. 10 - A 55-g mouse runs out to the end of the 17-cm-long...Ch. 10 - You have your bicycle upside down for repairs. The...Ch. 10 - Section 10.3 Rotational Inertia and the Analog of...Ch. 10 - The shaft connecting a power plants turbine and...Ch. 10 - The chamber of a rock-tumbling machine is a hollow...Ch. 10 - A wheels diameter is 92 cm, and its rotational...Ch. 10 - Three equal masses m are located at the vertices...Ch. 10 - (a) Estimate Earths rotational inertia, assuming...Ch. 10 - A neutron star is an extremely dense, rapidly...Ch. 10 - A 108-g Frisbee is 24 cm in diameter and has half...Ch. 10 - At the MIT Magnet Laboratory, energy is stored in...Ch. 10 - Section 10.4 Rotational Energy A 25-cm-diameter...Ch. 10 - Humankind uses energy at the rate of about 16 TW....Ch. 10 - A 150-g baseball is pitched at 33 m/s spinning at...Ch. 10 - (a) Find the energy stored in the flywheel of...Ch. 10 - A solid 2.4-kg sphere is rolling at 5.0 m/s. Find...Ch. 10 - What fraction of a solid disks kinetic energy is...Ch. 10 - A rolling ball has total kinetic energy 100 J, 40...Ch. 10 - A wheel turns through 2.0 revolutions while...Ch. 10 - Youre an engineer designing kitchen appliances,...Ch. 10 - An eagle with 2.1-m wingspan flaps its wings 20...Ch. 10 - A compact disc (CD) player varies the rotation...Ch. 10 - You rev your cars engine and watch the tachometer...Ch. 10 - A circular saw spins at 5800 rpm, and its...Ch. 10 - Full-circle rotation is common in mechanical...Ch. 10 - A pulley 12 cm in diameter is free to rotate about...Ch. 10 - A square frame is made from four thin rods, each...Ch. 10 - A thick ring has inner radius 12R, outer radius R,...Ch. 10 - A uniform rectangular flat plate has mass M and...Ch. 10 - Each propeller on a King Air twin-engine airplane...Ch. 10 - The cellular motor driving the flagellum in E....Ch. 10 - Verify by direct integration Table 10.2s entry for...Ch. 10 - Prob. 55PCh. 10 - A skaters body has rotational inertia 4.2 kgm2...Ch. 10 - A 2.4-kg block rests on a slope and is attached by...Ch. 10 - Youve got your bicycle upside down for repairs,...Ch. 10 - A potters wheel is a stone disk 90 cm in diameter...Ch. 10 - A ships anchor weighs 5.0kN. Its cable passes over...Ch. 10 - Starting from rest, a hollow ball rolls down a...Ch. 10 - A hollow ball rolls along a horizontal surface at...Ch. 10 - As an automotive engineer, youre charged with...Ch. 10 - A solid ball of mass M and radius R starts at rest...Ch. 10 - A disk of radius R has an initial mass M. Then a...Ch. 10 - A 50-kg mass is tied to a massless rope wrapped...Ch. 10 - Each wheel of a 320-kg motorcycle is 52 cm in...Ch. 10 - A solid marble starts from rest and rolls without...Ch. 10 - A disk of radius R and thickness w has a mass...Ch. 10 - The disk in Fig. 10.29 is rotating freely about a...Ch. 10 - Youre asked to check the specifications for a wind...Ch. 10 - In bicycling, each foot pushes on the pedal for...Ch. 10 - Prob. 73PCh. 10 - A thick ring of mass M has inner radius R1 and...Ch. 10 - A thin rod of length L and mass M is free to pivot...Ch. 10 - The local historical society has asked your...Ch. 10 - Youre skeptical about a new hybrid car that stores...Ch. 10 - Figure 10.31 shows an object of mass M with one...Ch. 10 - Figure 10.32 shows an apparatus used to measure...Ch. 10 - Centrifuges are widely used in biology and...Ch. 10 - Centrifuges are widely used in biology and...Ch. 10 - Centrifuges are widely used in biology and...Ch. 10 - Centrifuges are widely used in biology and...Ch. 10 - Centrifuges are widely used in biology and...
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