Principles of Physics: A Calculus-Based Text
5th Edition
ISBN: 9781133104261
Author: Raymond A. Serway, John W. Jewett
Publisher: Cengage Learning
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Chapter 7, Problem 38P
(a)
To determine
To determine: The number of times must the student run the flight of stairs to lose
(b)
To determine
To determine: The average power output in Watt and in horsepower, as he runs up the stairs.
(c)
To determine
To determine: Whether this activity in itself a practical way to lose weight.
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Chapter 7 Solutions
Principles of Physics: A Calculus-Based Text
Ch. 7.1 - By what transfer mechanisms does energy enter and...Ch. 7.1 - Consider a block sliding over a horizontal surface...Ch. 7.2 - Prob. 7.3QQCh. 7.2 - Prob. 7.4QQCh. 7.4 - Prob. 7.5QQCh. 7 - You hold a slingshot at arms length, pull the...Ch. 7 - An athlete jumping vertically on a trampoline...Ch. 7 - Prob. 3OQCh. 7 - Two children stand on a platform at the top of a...Ch. 7 - Answer yes or no to each of the following...
Ch. 7 - A ball of clay falls freely to the hard floor. It...Ch. 7 - What average power is generated by a 70.0-kg...Ch. 7 - In a laboratory model of cars skidding to a stop,...Ch. 7 - At the bottom of an air track tilted at angle , a...Ch. 7 - One person drops a ball from the top of a building...Ch. 7 - Prob. 2CQCh. 7 - Does everything have energy? Give the reasoning...Ch. 7 - Prob. 4CQCh. 7 - Prob. 5CQCh. 7 - Prob. 6CQCh. 7 - A block is connected to a spring that is suspended...Ch. 7 - Consider the energy transfers and transformations...Ch. 7 - Prob. 9CQCh. 7 - Prob. 10CQCh. 7 - Prob. 1PCh. 7 - Prob. 2PCh. 7 - Review. A bead slides without friction around a...Ch. 7 - At 11:00 a.m, on September 7, 2001, more than one...Ch. 7 - A block of mass 0.250 kg is placed on top of a...Ch. 7 - A block of mass m = 5.00 kg is released from point...Ch. 7 - Two objects are connected by a light string...Ch. 7 - Prob. 8PCh. 7 - Prob. 9PCh. 7 - Prob. 10PCh. 7 - Prob. 11PCh. 7 - A crate of mass 10.0 kg is pulled up a rough...Ch. 7 - Prob. 13PCh. 7 - Prob. 14PCh. 7 - A block of mass m = 2.00 kg is attached to a...Ch. 7 - Prob. 16PCh. 7 - A smooth circular hoop with a radius of 0.500 m is...Ch. 7 - Prob. 18PCh. 7 - Prob. 19PCh. 7 - As shown in Figure P7.20, a green bead of mass 25...Ch. 7 - A 5.00-kg block is set into motion up an inclined...Ch. 7 - The coefficient of friction between the block of...Ch. 7 - Prob. 23PCh. 7 - Prob. 24PCh. 7 - Prob. 25PCh. 7 - Prob. 26PCh. 7 - A child of mass m starts from rest and slides...Ch. 7 - The electric motor of a model train accelerates...Ch. 7 - Prob. 29PCh. 7 - Prob. 30PCh. 7 - Prob. 31PCh. 7 - Sewage at a certain pumping station is raised...Ch. 7 - Prob. 33PCh. 7 - Prob. 34PCh. 7 - Prob. 35PCh. 7 - Prob. 36PCh. 7 - Prob. 37PCh. 7 - Prob. 38PCh. 7 - Prob. 39PCh. 7 - Prob. 40PCh. 7 - A loaded ore car has a mass of 950 kg and rolls on...Ch. 7 - Prob. 42PCh. 7 - A certain automobile engine delivers 2.24 104 W...Ch. 7 - Prob. 44PCh. 7 - A small block of mass m = 200 g is released from...Ch. 7 - Prob. 46PCh. 7 - Prob. 47PCh. 7 - Prob. 48PCh. 7 - Prob. 49PCh. 7 - Prob. 50PCh. 7 - Prob. 51PCh. 7 - Prob. 52PCh. 7 - Jonathan is riding a bicycle and encounters a hill...Ch. 7 - Prob. 54PCh. 7 - A horizontal spring attached to a wall has a force...Ch. 7 - Prob. 56PCh. 7 - Prob. 57PCh. 7 - Prob. 58PCh. 7 - Prob. 59PCh. 7 - Prob. 60PCh. 7 - Prob. 61PCh. 7 - Prob. 62PCh. 7 - Make an order-of-magnitude estimate of your power...Ch. 7 - Prob. 64PCh. 7 - Prob. 65PCh. 7 - Review. As a prank, someone has balanced a pumpkin...Ch. 7 - Review. The mass of a car is 1 500 kg. The shape...Ch. 7 - A 1.00-kg object slides to the right on a surface...Ch. 7 - A childs pogo stick (Fig. P7.69) stores energy in...Ch. 7 - Prob. 70PCh. 7 - Prob. 71PCh. 7 - Prob. 72PCh. 7 - A block of mass m1 = 20.0 kg is connected to a...Ch. 7 - Prob. 74PCh. 7 - Prob. 75PCh. 7 - Prob. 76PCh. 7 - Prob. 77PCh. 7 - Prob. 78PCh. 7 - A block of mass 0.500 kg is pushed against a...Ch. 7 - A pendulum, comprising a light string of length L...Ch. 7 - Jane, whose mass is 50.0 kg, needs to swing across...Ch. 7 - A roller-coaster car shown in Figure P7.82 is...Ch. 7 - Prob. 83P
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