Please solve all of 5 Aaronson Practice problems on potential energy1. A 70.0 kg man jumping from a window lands in an elevated fire rescue net 11.0 m below the window. He momen-tarily stops when he has stretched the net by 1.50 m. Assuming that mechanical energy is conserved during thisprocess and the net acts like an ideal spring, find the elastic potential energy of the net when it is stretched by 1.50 m.Answer: 8580J3. The potential energy of a diatomic molecule (a two-atom system like H2) is given by:U = -B%3Dwhere r is the distance of separation of the two atoms. This potential energy is associated with the force that binds thetwo atoms together, the "Leonard-Jones" potential.a) Find the equilibrium separation, the distance between the atoms at which the force on each atom is zero.b) Is this force repulsive (pushing the atoms apart) or attractive (bringing the atoms together) if their separa-tion is smaller than the equilibrium separation? What if it is larger?Answer: a) (2 "4. A spring with a spring constant of 3200 N/m is initially stretched until the elastic potential energy is 1.44 J(U=0 when there is no stretching of the spring). What is the change in elastic potential energy if the initial stretch ischanged to:a) a stretch of 2.0 cm,b) a compression of 2.0 cm,c) a compression of 4.0 cm?b) -0.80 JAnswers: a)-0.80Jc) 1.12 J5. A pendulum is made of a thin, rigid rod of length L= 2.00 m and negligible mass. One end of the rod is attached to%3Dthe ceiling and can pivot freely. The other end is attached to a ball of mass m = 5.00 kg. The rod is pulled aside to anangle of 0, = 30° and is released from rest. As the ball descends to its lowest point,%3Da) how much work does the gravitational force do on it, andb) what is the change in gravitational potential energy of the Earth-ball system?Let us that the gravitational potential energy at the lowest point is what we call zero. This is akin to setting the groundto be y = 0, and thus the gravitational potential energy at ground level is U= mgy=0.c) What was the gravitational potential energy of the ball just before it was released?d) Do the answers to parts a, b, and c of this question increase, decrease, or stay the same if the angle 0,is%3D%3Dincreased?Answers: a) 13.1J b) -13.1 J c) 13.1J d) increase, decrease, increase

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energy 1. A 70.0 kg man jumping from a window lands in an elevated fire rescue net 11.0 m below the window. He momen- tarily stops when he has stretched the net by 1.50 m. Assuming that mechanical energy is conserved during this process and the net acts like an ideal spring, find the elastic potential energy of the net when it is stretched by 1.50 m. Answer: 8580J

energy 1. A 70.0 kg man jumping from a window lands in an elevated fire rescue net 11.0 m below the window. He momen- tarily stops when he has stretched the net by 1.50 m. Assuming that mechanical energy is conserved during this process and the net acts like an ideal spring, find the elastic potential energy of the net when it is stretched by 1.50 m. Answer: 8580J

Physics for Scientists and Engineers: Foundations and Connections

1st Edition

ISBN:9781133939146

Author:Katz, Debora M.

Publisher:Katz, Debora M.

Chapter8: Conservation Of Energy

Section: Chapter Questions

Problem 24PQ: A block is placed on top of a vertical spring, and the spring compresses. Figure P8.24 depicts a...

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