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 28P
The electric motor of a model train accelerates the train from rest to 0.620 m/s in 21.0 ms. The total mass of the train is 875 g. (a) Find the minimum power delivered to the train by electrical transmission from the metal rails during the acceleration. (b) Why is it the minimum power?
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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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- What average power is generated by a 70.0-kg mountain climber who climbs a summit of height 325 m in 95.0 min? (a) 39.1 W (b) 54.6 W (c) 25.5 W (d) 67.0 W (e) 88.4 Warrow_forwardA person in good physical condition can put out 100 W of useful power for several hours at a stretch, perhaps by pedaling a mechanism that drives an electric generator. Neglecting any problems of generator efficiency and practical considerations such as resting time: (a) How many people ‘would it take to nm a 4.O0-kW electric clothes dryer? (b) How many people would it take to replace a large electric power plant that generates 800 MW?arrow_forwardA person in good physical condition can put out 100 W of useful power for several hours at a stretch, perhaps by pedaling a mechanism that drives an electric generator. Neglecting any problems of generator efficiency and practical considerations such as resting time: (a) How many people would it take to run a 4.00-kW electric clothes dryer? (b) How many people would it take to replace a large electric power plant that generates 800 MW?arrow_forward
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