Essential University Physics: Volume 1 (3rd Edition)
3rd Edition
ISBN: 9780321993724
Author: Richard Wolfson
Publisher: PEARSON
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Textbook Question
Chapter 6, Problem 78P
Your friend does five reps with a barbell, on each rep lifting 45 kg 0.50 m. She claims the work done is enough to “burn off” a chocolate bar with energy content 230 kcal (see Exercise 33). Is that true? If not, how many lifts would it take?
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Chapter 6 Solutions
Essential University Physics: Volume 1 (3rd Edition)
Ch. 6.2 - Two objects are each displaced the same distance,...Ch. 6.3 - Three forces have magnitudes in newtons that are...Ch. 6.4 - For each situation, tell whether the net work done...Ch. 6 - Give two examples of situations in which you might...Ch. 6 - If the scalar product of two nonzero vectors is...Ch. 6 - Must you do work to whirl a ball around on the end...Ch. 6 - If you pick up a suitcase and put it down, how...Ch. 6 - You want to raise a piano a given height using a...Ch. 6 - Does the gravitational force of the Sun do work on...Ch. 6 - A pendulum bob swings back and forth on the end of...
Ch. 6 - Does your cars kinetic energy change if you drive...Ch. 6 - A watt-second is a unit of what quantity? Relate...Ch. 6 - A truck is moving northward at 55 mi/h. Later, its...Ch. 6 - Is it possible for you to do work on an object...Ch. 6 - How much work do you do as you exert a 75-N force...Ch. 6 - If the coefficient of kinetic friction is 0.21,...Ch. 6 - A crane lifts a 650-kg beam vertically upward 23 m...Ch. 6 - The worlds highest waterfall, the Cherun-Meru in...Ch. 6 - A meteorite plunges to Earth, embedding itself 75...Ch. 6 - An elevator of mass m rises a vertical distance h...Ch. 6 - Prob. 19ECh. 6 - Find the work done by a force F = 1.8 + 2.2 N as...Ch. 6 - To push a stalled car, you apply a 470-N force at...Ch. 6 - Find the total work done by the force shown in...Ch. 6 - How much work does it take to stretch a spring...Ch. 6 - Uncompressed, the spring for an automobile...Ch. 6 - You do 8.5 J of work to stretch a spring with k =...Ch. 6 - Spider silk is a remarkable elastic material. A...Ch. 6 - Whats the kinetic energy of a 2.4105-kg airplane...Ch. 6 - Prob. 28ECh. 6 - At what speed must a 950-kg subcompact car be...Ch. 6 - A 60-kg skateboarder comes over the top of a hill...Ch. 6 - After a tornado, a 0.50-g drinking straw was found...Ch. 6 - From what height would you have to drop a car for...Ch. 6 - A typical human diet is 2000 calories per day,...Ch. 6 - A horse plows a 200-m-long furrow in 5.0 min,...Ch. 6 - A typical car battery stores about 1 kWh of...Ch. 6 - A sprinter completes a 100-m dash in 10.6 s. doing...Ch. 6 - How much work can a 3.5-hp lawnmower engine do in...Ch. 6 - A 75-kg long-jumper takes 3.1 s to reach a prejump...Ch. 6 - Estimate your power output as you do deep knee...Ch. 6 - In midday sunshine, solar energy strikes Earth at...Ch. 6 - It takes about 20 kJ to melt an ice cube. A...Ch. 6 - Prob. 42ECh. 6 - You slide a box of books at constant speed up a 30...Ch. 6 - Two people push a stalled car at its front doors,...Ch. 6 - Youre at the gym, doing arm raises. With each rep....Ch. 6 - A locomotive does 7.9 1011 J of work in pulling a...Ch. 6 - You pull a box 23 in horizontally, using the rope...Ch. 6 - Prob. 48PCh. 6 - (a) Find the scalar product of the vectors a + b...Ch. 6 - Looking to cut costs, the airline you work for...Ch. 6 - How much work does a force F = 67 + 23 + 55k N do...Ch. 6 - A force F Facts in the x-direction, its magnitude...Ch. 6 - A certain amount of work is required to stretch...Ch. 6 - A force with magnitude F = a x acts in the...Ch. 6 - The force exerted by a rubber band is given...Ch. 6 - You put your little sister (mass m) on a swing...Ch. 6 - Two unknown elementary particles pass through a...Ch. 6 - A tractor tows a plane from its airport gate,...Ch. 6 - E. coli bacteria swim by means of flagella that...Ch. 6 - On February 15, 2013, an asteroid moving at 19...Ch. 6 - An elevator ascends from the ground floor to the...Ch. 6 - Youre asked to assess the reliability of a nuclear...Ch. 6 - A force pointing in the x-direction is given by F...Ch. 6 - A force pointing in the x-direction is given by F...Ch. 6 - Two vectors have equal magnitude, and their scalar...Ch. 6 - At what rate can a half-horsepower well pump...Ch. 6 - The rate at which the United States imports oil,...Ch. 6 - By measuring oxygen uptake, sports physiologists...Ch. 6 - Youre writing performance specifications for a new...Ch. 6 - A 1400-kg car ascends a mountain road at a steady...Ch. 6 - You do 2.2 kJ of work pushing a 78-kg trunk at...Ch. 6 - (a) Find the work done in lifting 1 L of blood...Ch. 6 - (a) What power is needed to push a 95-kg crate at...Ch. 6 - You mix flour into bread dough, exerting a 45-N...Ch. 6 - A machine does work at a rate given by P = ct2,...Ch. 6 - A typical bumblebee has mass 0.25 mg. It beats its...Ch. 6 - Youre trying to decide whether to buy an...Ch. 6 - Your friend does five reps with a barbell, on each...Ch. 6 - A machine delivers power at a decreasing rate P =...Ch. 6 - A locomotive accelerates a freight train of total...Ch. 6 - A force given by F = b/x acts in the x-direction,...Ch. 6 - Youre assisting a cardiologist in planning a...Ch. 6 - Youre an engineer for a company that makes...Ch. 6 - You push an object of mass m slowly, partway up a...Ch. 6 - A particle moves from the origin to the point x =...Ch. 6 - Repeat Problem 85 for the following cases: (a) the...Ch. 6 - The worlds fastest elevator, in Taiwans Taipei 101...Ch. 6 - An experimental measurement of the force required...Ch. 6 - Youre an expert witness in a medical malpractice...Ch. 6 - The energy in a batted baseball comes from the...Ch. 6 - The energy in a batted baseball comes from the...Ch. 6 - The energy in a batted baseball comes from the...Ch. 6 - The energy in a batted baseball comes from the...
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