College Physics
2nd Edition
ISBN: 9780134601823
Author: ETKINA, Eugenia, Planinšič, G. (gorazd), Van Heuvelen, Alan
Publisher: Pearson,
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Textbook Question
Chapter 8, Problem 5RQ
Review Question 8.5 You are trying to hold a heavy dumbbell in one hand so that your arm is perpendicular to your body. Why is it easier to hold it with a bent arm than with a straight arm?
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topic: rotation of rigid bodies
A museum of modern art is displaying an irregular 426-N sculpture by hanging it from two thin vertical wires, A and B, that are 1.25 m apart. The center of gravity of this piece of art is 48.0 cm from its extreme right tip. Find the tension in each wire.
i need a detailed explanation please
topic: rotation of rigid bodies
A museum of modern art is displaying an irregular 426-N sculpture by hanging it from two thin vertical wires, A and B, that are 1.25 m apart. The center of gravity of this piece of art is 48.0 cm from its extreme right tip. Find the tension in each wire.
the answer should be the one in the picture but i need a more detailed explanation please.
Problem 1
A kugel fountain, also known as a floating sphere fountain, is a sculpture that suspends a large, typically stone, sphere on a thin surface of water. One of three in Columbus is on campus in the Chadwick Arboretum on the
corner of Lane Ave. and Olentangy. Kugel fountains have very little friction between the stone sphere and the hollow in which they sit, so it takes very little torque to start one moving from rest.
(A) The kugel fountain in the Richard and Annette Bloch Cancer Survivor’s Plaza in the
Lane Ave Gardens has a granite sphere with a mass of approximately 1,800 kg, and
a radius of about half a meter. You use your hand to apply a tangential force on the
sphere to start it rotating from rest, and it takes 12 seconds to complete a quarter
revolution. What is the average torque you applied to the sphere?
(B) What is the average magnitude of the tangential force you applied?
(C) Let’s consider if your answer is a reasonable amount of force for a person to exert.…
Chapter 8 Solutions
College Physics
Ch. 8 - Prob. 1RQCh. 8 - Review Question 8.2 Give an example of a situation...Ch. 8 - Review Question 8.3 You read the following...Ch. 8 - Prob. 4RQCh. 8 - Review Question 8.5 You are trying to hold a heavy...Ch. 8 - Review Question 8.6 Why is a ball hanging by a...Ch. 8 - A falling leaf usually flutters while falling....Ch. 8 - Prob. 2MCQCh. 8 - A hammock is tied with ropes between two trees. A...Ch. 8 - Prob. 4MCQ
Ch. 8 - 5. A physics textbook lies on top of a chemistry...Ch. 8 - What does it mean if the torque of a force is...Ch. 8 - Prob. 7MCQCh. 8 - 8. Why do you tilt your body forward when hiking...Ch. 8 - 9. What does it mean if the torque of a 10-N force...Ch. 8 - What is the maximum angle to the horizontal you...Ch. 8 - Prob. 11MCQCh. 8 - 12. Is it possible for an object not to be in...Ch. 8 - Explain the meaning of torque so that a friend not...Ch. 8 - Prob. 14CQCh. 8 - What are the two conditions of equilibrium? What...Ch. 8 - Give three examples of situations in which an...Ch. 8 - The force that the body muscles exert on bones...Ch. 8 - A ladder leans against a wall. Construct a force...Ch. 8 - Using a crowbar, a person can remove a nail by...Ch. 8 - 20. Is it more difficult to do a sit-up with your...Ch. 8 - Sit on a chair with your feet straight down at the...Ch. 8 - Can you balance the tip of a wooden ruler...Ch. 8 - Try to balance a sharp wooden pencil on your...Ch. 8 - 24. Design a device that you can use to...Ch. 8 - Explain why it is easier to keep your balance...Ch. 8 - A carpenters trick to keep nails from bending when...Ch. 8 - Determine the torques about the axis of rotation P...Ch. 8 - 2. Three 200-N forces are exerted on the beam...Ch. 8 - 3. * A 2.0-m-long, 15-kg ladder is resting against...Ch. 8 - Figure P8.4 shows two different situations where...Ch. 8 - Three friends tie three ropes in a knot and pull...Ch. 8 - Prob. 6PCh. 8 - * Kate joins Jim, Luis, and Adrienne in the...Ch. 8 - You hang a light in front of your house using an...Ch. 8 - * Find the values of the forces the ropes exert on...Ch. 8 - Prob. 10PCh. 8 - Determine the masses m1 and m2 of the two objects...Ch. 8 - * Lifting an engine You work in a machine shop and...Ch. 8 - 13. * More lifting You exert a 630-N force on rope...Ch. 8 - Prob. 14PCh. 8 - 15. * Tightrope walking A tightrope walker wonders...Ch. 8 - 16. * Lifting patients An apparatus to lift...Ch. 8 - 17. A father (80 kg), mother (56 kg), daughter (16...Ch. 8 - Prob. 18PCh. 8 - * You place a 3.0-m-long board symmetrically...Ch. 8 - Prob. 20PCh. 8 - Prob. 21PCh. 8 - Prob. 22PCh. 8 - 23. EST Compare the two different designs of...Ch. 8 - Ray decides to paint the outside of his uncles...Ch. 8 - 25. * A 2.0-m-long uniform beam of mass 8.0 kg...Ch. 8 - * A uniform beam of length / and mass m supports a...Ch. 8 - Prob. 27PCh. 8 - Prob. 28PCh. 8 - Prob. 29PCh. 8 - Prob. 30PCh. 8 - 31. * An 80-kg clown sits on a 20-kg bike on a...Ch. 8 - s center of mass? (Hint: You can think of cutting...Ch. 8 - Leg support A persons broken leg is kept in place...Ch. 8 - Prob. 34PCh. 8 - Prob. 35PCh. 8 - * If the force F shown in Figure P8.35 is 840 N...Ch. 8 - Prob. 37PCh. 8 - 38. * You decide to hang another plant from a...Ch. 8 - Prob. 39PCh. 8 - * What mechanical work must you do to lift a log...Ch. 8 - 41. * A 70-g meter stick has a 30-g piece of...Ch. 8 - * You are trying to tilt a very tall refrigerator...Ch. 8 - Prob. 43PCh. 8 - 44. * You have an Atwood machine (see Figure 4.9 )...Ch. 8 - * EST You stand sideways in a moving train....Ch. 8 - 46. EST Your hand holds a liter of milk (mass...Ch. 8 - EST Body torque You hold a 4.0-kg computer....Ch. 8 - Prob. 48GPCh. 8 - 49. BIO Using triceps to push a table A man pushes...Ch. 8 - Prob. 50GPCh. 8 - Prob. 51GPCh. 8 - Prob. 52GPCh. 8 - 53.* BIO Dumbbell lift IA woman lifts a 3.6-kg...Ch. 8 - s shoulder joint exerts on her humerus.Ch. 8 - Prob. 55GPCh. 8 - * Eiichi has purchased an adjustable hand grip to...Ch. 8 - 57. *BIO While browsing books on neurophysiology,...Ch. 8 - 58. ** Touch detector You have two force sensors...Ch. 8 - * An 80-kg person stands at one end of a 130-kg...Ch. 8 - 61. EST Two people (50 kg and 75 kg) holding hands...Ch. 8 - Prob. 62GPCh. 8 - BIO Muscles work in pairs Skeletal muscles produce...Ch. 8 - BIO Muscles work in pairs Skeletal muscles produce...Ch. 8 - BIO Muscles work in pairs Skeletal muscles produce...Ch. 8 - BIO Muscles work in pairs Skeletal muscles produce...Ch. 8 - BIO Improper lifting and the back A careful study...Ch. 8 - BIO Improper lifting and the back A careful study...Ch. 8 - BIO Improper lifting and the back A careful study...Ch. 8 - BIO Improper lifting and the back A careful study...
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What is Torque? | Physics | Extraclass.com; Author: Extraclass Official;https://www.youtube.com/watch?v=zXxrAJld9mo;License: Standard YouTube License, CC-BY