COLLEGE PHYSICS:STRATEGIC APPR.W/ACCESS
1st Edition
ISBN: 9781323844717
Author: KNIGHT&JONES
Publisher: PEARSON C
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Textbook Question
Chapter 7, Problem 24P
A professor’s office door is 0.91 m wide, 2.0 m high, and 4.0 cm thick; has a mass of 25 kg; and pivots on frictionless hinges. A “door closer” is attached to the door and the top of the door frame. When the door is open and at rest, the door closer exerts a torque of 5.2 N · m. What is the least force that you need to apply to the door to hold it open?
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Chapter 7 Solutions
COLLEGE PHYSICS:STRATEGIC APPR.W/ACCESS
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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