College Physics: A Strategic Approach (4th Edition)
4th Edition
ISBN: 9780134609034
Author: Randall D. Knight (Professor Emeritus), Brian Jones, Stuart Field
Publisher: PEARSON
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Chapter 7, Problem 4CQ
If you are using a wrench to loosen a very stubborn nut, you can make the job easier by using a “cheater pipe.” This is a piece of pipe that slides over the handle of the wrench, as shown in Figure Q7.4, making it effectively much longer. Explain why this would help you loosen the nut.
Figure Q7.4
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Q2. In Figure Q2, ropes AB and AC are tied at point A which is 5 m from the base of the tree,
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a
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F.
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Chapter 7 Solutions
College Physics: A Strategic Approach (4th Edition)
Ch. 7 - The batter in a baseball game hits a home run. As...Ch. 7 - Viewed from somewhere in space above the north...Ch. 7 - Figure Q7.3 shows four pulleys, each with a heavy...Ch. 7 - If you are using a wrench to loosen a very...Ch. 7 - Prob. 5CQCh. 7 - Prob. 6CQCh. 7 - Prob. 7CQCh. 7 - A screwdriver with a very thick handle requires...Ch. 7 - If you have ever driven a truck, you likely found...Ch. 7 - A student gives a steady push to a ball at the end...
Ch. 7 - Prob. 11CQCh. 7 - If you grasp a hammer by its lightweight handle...Ch. 7 - Prob. 13CQCh. 7 - Prob. 15CQCh. 7 - The moment of inertia of a uniform rod about an...Ch. 7 - Prob. 17CQCh. 7 - With care, its possible to walk on top of a barrel...Ch. 7 - A nut needs to be tightened with a wrench. Which...Ch. 7 - Prob. 20MCQCh. 7 - Prob. 21MCQCh. 7 - Prob. 22MCQCh. 7 - Prob. 23MCQCh. 7 - A typical compact disk has a mass of 15 g and a...Ch. 7 - Two horizontal rods are each held up by vertical...Ch. 7 - Prob. 26MCQCh. 7 - Questions 25 through 27 concern a classic...Ch. 7 - Questions 25 through 27 concern a classic...Ch. 7 - Questions 25 through 27 concern a classic...Ch. 7 - What is the angular position in radians of the...Ch. 7 - A child on a merry-go-round takes 3.0 s to go...Ch. 7 - What is the angular speed of the tip of the minute...Ch. 7 - An old-fashioned vinyl record rotates on a...Ch. 7 - The earths radius is about 4000 miles. Kampala,...Ch. 7 - Prob. 6PCh. 7 - A turntable rotates counterclockwise at 78 rpm. A...Ch. 7 - Prob. 8PCh. 7 - Prob. 9PCh. 7 - Prob. 10PCh. 7 - The 1.00-cm-long second hand on a watch rotates...Ch. 7 - The earths radius is 6.37 106 m; it rotates once...Ch. 7 - To throw a discus, the thrower holds it with a...Ch. 7 - Prob. 14PCh. 7 - A computer hard disk starts from rest, then speeds...Ch. 7 - Prob. 16PCh. 7 - The crankshaft in a race car goes from rest to...Ch. 7 - Reconsider the situation in Example 7.10. If Luis...Ch. 7 - Prob. 19PCh. 7 - Prob. 20PCh. 7 - What is the net torque about the axle on the...Ch. 7 - The tune-up specifications of a car call for the...Ch. 7 - In Figure P7.22, force F2, acts half as far from...Ch. 7 - A professors office door is 0.91 m wide, 2.0 m...Ch. 7 - What is the net torque on the bar shown in Figure...Ch. 7 - Prob. 26PCh. 7 - Prob. 27PCh. 7 - Prob. 28PCh. 7 - What is the net torque on the bar shown in Figure...Ch. 7 - Prob. 30PCh. 7 - The 2.0 kg, uniform, horizontal rod in Figure...Ch. 7 - A 4.00-m-long, 500 kg steel beam extends...Ch. 7 - An athlete at the gym holds a 3.0 kg steel ball in...Ch. 7 - The 2.0-m-long, 15 kg beam in Figure P7.34 is...Ch. 7 - Prob. 35PCh. 7 - Hold your arm outstretched so that it is...Ch. 7 - Prob. 37PCh. 7 - Prob. 38PCh. 7 - A regulation table tennis ball is a thin spherical...Ch. 7 - Prob. 40PCh. 7 - A solid cylinder with a radius of 4.0 cm has the...Ch. 7 - Prob. 42PCh. 7 - A bicycle rim has a diameter of 0.65 m and a...Ch. 7 - Prob. 44PCh. 7 - A small grinding wheel has a moment of inertia of...Ch. 7 - Prob. 46PCh. 7 - An objects moment of inertia is 2.0 kg m2. Its...Ch. 7 - Prob. 48PCh. 7 - A 200 g, 20-cm-diameter plastic disk is spun on an...Ch. 7 - Prob. 50PCh. 7 - A frictionless pulley, which can be modeled as a...Ch. 7 - Prob. 52PCh. 7 - If you lift the front wheel of a poorly maintained...Ch. 7 - Prob. 54PCh. 7 - A toy top with a spool of diameter 5.0 cm has a...Ch. 7 - Prob. 56PCh. 7 - A bicycle with 0.80-m-diameter tires is coasting...Ch. 7 - Prob. 58PCh. 7 - Prob. 59PCh. 7 - Prob. 60PCh. 7 - Prob. 61GPCh. 7 - The grap in Figure P7.56 shows the angular...Ch. 7 - A car with 58-cm-diameter tires accelerates...Ch. 7 - The cable lifting an elevator is wrapped around a...Ch. 7 - The 20-cm-diameter disk in Figure P7.59 can rotate...Ch. 7 - A combination lock has a 1.0-cm-diameter knob that...Ch. 7 - A 70 kg mans arm, including the hand, can be...Ch. 7 - Prob. 68GPCh. 7 - A reasonable estimate of the moment of inertia of...Ch. 7 - Prob. 70GPCh. 7 - The ropes in Figure P7.65 are each wrapped around...Ch. 7 - Flywheels are large, massive wheels used to store...Ch. 7 - A 1.0 kg ball and a 2.0 kg ball are connected by a...Ch. 7 - Prob. 76GPCh. 7 - A tradesman sharpens a knife by pushing it with a...Ch. 7 - MCAT-Style Passage Problems The Bunchberry The...Ch. 7 - The Bunchberry The bunchberry flower has the...Ch. 7 - The Bunchberry The bunchberry flower has the...Ch. 7 - Prob. 81MSPPCh. 7 - Prob. 82MSPPCh. 7 - Prob. 83MSPPCh. 7 - Prob. 84MSPP
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