University Physics (14th Edition)
14th Edition
ISBN: 9780133969290
Author: Hugh D. Young, Roger A. Freedman
Publisher: PEARSON
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Textbook Question
Chapter 7, Problem 7.36E
A marble moves along the x-axis. The potential-energy function is shown in Fig. E7.36. (a) At which of the labeled x-coordinates is the force on the marble zero? (b) Which of the labeled x-coordinates is a position of stable equilibrium? (c) Which of the labeled x-coordinates is a position of unstable equilibrium?
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The potential energy function for a system of particles is given by U(x) = -x3 + 2x2 + 3x, where x is the position of one particle in the system. (a) Determine the force Fx on the particle as a function of x. (b) For what values of x is theforce equal to zero? (c) Plot U(x) versus x and Fx versus x and indicate points of stable and unstable equilibrium.
The potential energy of a system is given by:
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Chapter 7 Solutions
University Physics (14th Edition)
Ch. 7 - A baseball is thrown straight up with initial...Ch. 7 - A projectile has the same initial kinetic energy...Ch. 7 - An object is released from rest at the top of a...Ch. 7 - An egg is released from rest from the roof of a...Ch. 7 - A physics teacher had a howling hall suspended...Ch. 7 - Is it possible for a friction force to increase...Ch. 7 - A woman bounces on a trampoline, going a little...Ch. 7 - Q7.8 Fractured Physics. People often call their...Ch. 7 - (a) A book is lifted upward a vertical distance of...Ch. 7 - (a) A block of wood is pushed against a spring,...
Ch. 7 - A 1.0-kg stone and a 10.0-kg stone are released...Ch. 7 - Two objects with different masses are launched...Ch. 7 - When people are cold, they often rub their hands...Ch. 7 - A box slides down a ramp and work is done on the...Ch. 7 - In physical terms, explain why friction is a...Ch. 7 - Since only changes in potential energy are...Ch. 7 - Figure 7.22a shows the potential-energy function...Ch. 7 - Figure 7.22b shows the potential-energy function...Ch. 7 - For a system of two particles we often let the...Ch. 7 - Explain why the points x = A and x = A in Fig....Ch. 7 - A particle is in neutral equilibrium if the net...Ch. 7 - The net force on a particle of mass m has the...Ch. 7 - The potential-energy function for a force F is...Ch. 7 - In one day, a 75-kg mountain climber ascends from...Ch. 7 - BIO How High Can We Jump? The maximum height a...Ch. 7 - CP A 90.0-kg mail bag hangs by a vertical rope 3.5...Ch. 7 - BIO Food Calories. The food calorie, equal to 4186...Ch. 7 - A baseball is thrown from the roof of a...Ch. 7 - A crate of mass M starts from rest at the top of a...Ch. 7 - BIO Human Energy vs. Insect Energy. For its size,...Ch. 7 - Prob. 7.8ECh. 7 - Prob. 7.9ECh. 7 - A 25.0-kg child plays on a swing having support...Ch. 7 - You are testing a new amusement park roller...Ch. 7 - Tarzan and Jane. Tarzan, in one tree, sights Jane...Ch. 7 - CP A 10.0-kg microwave oven is pushed 6.00 m up...Ch. 7 - An ideal spring of negligible mass is 12.00 cm...Ch. 7 - A force of 520 N keeps a certain spring stretched...Ch. 7 - BIO Tendons. Tendons are strong elastic fibers...Ch. 7 - A spring stores potential energy U0 when it is...Ch. 7 - A slingshot will shoot a 10-g pebble 22.0 m...Ch. 7 - A spring of negligible mass has force constant k =...Ch. 7 - A 1.20-kg piece of cheese is placed on a vertical...Ch. 7 - A spring of negligible mass has force constant k =...Ch. 7 - (a) For the elevator of Example 7.9 (Section 7.2),...Ch. 7 - A 2.50-kg mass is pushed against a horizontal...Ch. 7 - A 2.50-kg block on a horizontal floor is attached...Ch. 7 - You are asked to design a spring that will give a...Ch. 7 - A 75-kg roofer climbs a vertical 7.0-m ladder to...Ch. 7 - A 0.60-kg book slides on a horizontal table. The...Ch. 7 - CALC In an experiment, one of the forces exerted...Ch. 7 - A 62.0-kg skier is moving at 6.50 m/s on a...Ch. 7 - Prob. 7.30ECh. 7 - CALC A force parallel to the .v-axis acts on a...Ch. 7 - CALC The potential energy of a pair of hydrogen...Ch. 7 - CALC A small block with mass 0.0400 kg is moving...Ch. 7 - CALC An object moving in the xy-plane is acted on...Ch. 7 - CALC The potential energy of two atoms in a...Ch. 7 - A marble moves along the x-axis. The...Ch. 7 - At a construction site, a 65.0-kg bucket of...Ch. 7 - Two blocks with different masses are attached to...Ch. 7 - A block with mass 0.50 kg is forced against a...Ch. 7 - A 2.00-kg block is pushed against a spring with...Ch. 7 - A 2.00-kg block is pushed against a spring with...Ch. 7 - CP Riding a Loop-the- Loop. A car in an amusement...Ch. 7 - A 2.0-kg piece of wood slides on a curved surface...Ch. 7 - Up and Down the Hill. A 28-kg rock approaches the...Ch. 7 - A 15.0-kg stone slides down a snow-covered hill...Ch. 7 - CP A 2.8-kg block slides over the smooth, icy hill...Ch. 7 - Bungee Jump. A bungee cord is 30.0 m long and,...Ch. 7 - You are designing a delivery ramp for crates...Ch. 7 - The Great Sandini is a 60-kg circus performer who...Ch. 7 - A 1500-kg rocket is to be launched with an initial...Ch. 7 - A system of two paint buckets connected by a...Ch. 7 - These results are from a computer simulation for a...Ch. 7 - CP A 0.300-kg potato is tied to a string with...Ch. 7 - A 60.0-kg skier starts from rest at the top of a...Ch. 7 - Prob. 7.55PCh. 7 - A ball is thrown upward with an initial velocity...Ch. 7 - Prob. 7.57PCh. 7 - A truck with mass m has a brake failure while...Ch. 7 - CALC A certain spring found not to obey Hookes law...Ch. 7 - CP A sled with rider having a combined mass of 125...Ch. 7 - CALC A conservative force F is in the +x-direction...Ch. 7 - A 3.00-kg block is connected to two ideal...Ch. 7 - A 0.150-kg block of ice is placed against a...Ch. 7 - If a fish is attached to a vertical spring and...Ch. 7 - CALC You are an industrial engineer with a...Ch. 7 - A basket of negligible weight hangs from a...Ch. 7 - CALC A 3.00-kg fish is attached to the lower end...Ch. 7 - You are designing an amusement park ride. A cart...Ch. 7 - A 0.500-kg block, attached to a spring with length...Ch. 7 - CP A small block with mass 0.0400 kg slides in a...Ch. 7 - CP A small block with mass 0.0500 kg slides in a...Ch. 7 - CP Pendulum. A small rock with mass 0.12 kg is...Ch. 7 - A wooden block with mass 1.50 kg is placed against...Ch. 7 - CALC A small object with mass m = 0.0900 kg moves...Ch. 7 - CALC A cutting tool under microprocessor control...Ch. 7 - A particle moves along the x-axis while acted on...Ch. 7 - Prob. 7.77PCh. 7 - DATA A long ramp made of cast iron is sloped at a...Ch. 7 - DATA A single conservative force F(x) acts on a...Ch. 7 - CALC A proton with mass m moves in one dimension....Ch. 7 - BIO THE DNA SPRING. A DNA molecule, with its...Ch. 7 - BIO THE DNA SPRING. A DNA molecule, with its...Ch. 7 - BIO THE DNA SPRING. A DNA molecule, with its...Ch. 7 - BIO THE DNA SPRING. A DNA molecule, with its...
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