University Physics (14th Edition)
14th Edition
ISBN: 9780133969290
Author: Hugh D. Young, Roger A. Freedman
Publisher: PEARSON
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Textbook Question
Chapter 11, Problem Q11.7DQ
You can probably stand flatfooted on the floor and then rise up and balance on your tiptoes. Why are you unable do it if your toes are touching the wall of your room? (Try it!)
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Stand with your heels and back against a wall and try to bend over and touch your toes. You’ll find that you have to stand away from the wall to do so without toppling over. Compare the minimum distance of your heels from the wall with the distance for a friend of the opposite sex. Who can touch their toes with their heels nearer to the wall: men or women? On the average and in proportion to height, which sex has the lower center of gravity?
Chapter 11 Solutions
University Physics (14th Edition)
Ch. 11 - Does a rigid object in uniform rotation about a...Ch. 11 - (a) Is it possible for an object to be in...Ch. 11 - Prob. Q11.3DQCh. 11 - Does the center of gravity of a solid body always...Ch. 11 - Prob. Q11.5DQCh. 11 - You are balancing a wrench by suspending it at a...Ch. 11 - You can probably stand flatfooted on the floor and...Ch. 11 - Prob. Q11.8DQCh. 11 - An object consists of a ball of weight W glued to...Ch. 11 - Prob. Q11.10DQ
Ch. 11 - Prob. Q11.11DQCh. 11 - In pioneer days, when a Conestoga wagon was stuck...Ch. 11 - The mighty Zimbo claims to have leg muscles so...Ch. 11 - Why is it easier to hold a 10-kg dumbbell in your...Ch. 11 - Certain features of a person, such as height and...Ch. 11 - During pregnancy, women often develop back pains...Ch. 11 - Why is a tapered water glass with a narrow base...Ch. 11 - Prob. Q11.18DQCh. 11 - A uniform beam is suspended horizontally and...Ch. 11 - If a metal wire has its length doubled and its...Ch. 11 - A metal wire of diameter D stretches by 0.100 mm...Ch. 11 - Prob. Q11.22DQCh. 11 - The material in human bones and elephant bones is...Ch. 11 - There is a small bui appreciable amount of elastic...Ch. 11 - When rubber mounting blocks are used to absorb...Ch. 11 - A 0.120-kg. 50.0-cm-long uniform bar has a small...Ch. 11 - Prob. 11.2ECh. 11 - A uniform rod is 2.00 m long and has mass 1.80 kg....Ch. 11 - A uniform 300-N trapdoor in a floor is hinged at...Ch. 11 - Raising a Ladder. A ladder carried by a fire truck...Ch. 11 - Two people are carrying a uniform wooden board...Ch. 11 - Two people carry a heavy electric motor by placing...Ch. 11 - A 60.0-cm. uniform. 50.0-N shelf is supported...Ch. 11 - A 350-N, uniform. 1.50-m bar is suspended...Ch. 11 - A uniform ladder 5.0 m long rests against a...Ch. 11 - A diving board 3.00 m long is supported at a point...Ch. 11 - A uniform aluminum beam 9.00 m long, weighing 300...Ch. 11 - Find the tension T in each cable and the magnitude...Ch. 11 - The horizontal beam in Fig. E11.14 weighs 190 N....Ch. 11 - The boom shown in Fig. E11.15 weighs 2600 N and is...Ch. 11 - Suppose that you can lift no more than 650 N...Ch. 11 - A 9.00-m-long uniform beam is hinged to a vertical...Ch. 11 - A 15,000-N crane pivots around a friction-free...Ch. 11 - A 3.00-m-long. 190-N, uniform rod at the zoo is...Ch. 11 - A nonuniform beam 4.50 m long and weighing 1.40 kN...Ch. 11 - A Couple. 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The...Ch. 11 - A square steel plate is 10.0 cm on a side and...Ch. 11 - In lab tests on a 9.25-cm cube of a certain...Ch. 11 - A brass wire is to withstand a tensile force of...Ch. 11 - In a materials testing laboratory, a metal wire...Ch. 11 - A 4.0-m-long steel wire has a cross-sectional area...Ch. 11 - CP A steel cable with cross-sectional area 3.00...Ch. 11 - A door 1.00 m wide and 2.00 m high weighs 330 N...Ch. 11 - A box of negligible mass rests at the lett end of...Ch. 11 - Sir Lancelot rides slowly out of the castle at...Ch. 11 - Mountain Climbing. Mountaineers often use a rope...Ch. 11 - A uniform, 8.0-m, 1150-kg beam is hinged to a wall...Ch. 11 - A uniform, 255.N rod that is 2.00 m long carries a...Ch. 11 - A claw hammer is used to pull a nail out of a...Ch. 11 - You open a restaurant and hope to entice customers...Ch. 11 - End A of the bar AB in Fig. P11.50 rests on a...Ch. 11 - BIO Supporting a Broken Leg. A therapist tells a...Ch. 11 - A Truck on a Drawbridge. A loaded cement mixer...Ch. 11 - BIO Leg Raises. In a simplified version of the...Ch. 11 - BIO Pumping Iron. A 72.0-kg weightlifter doing arm...Ch. 11 - Prob. 11.55PCh. 11 - You are asked to design the decorative mobile...Ch. 11 - A uniform, 7.5-m-long beam weighing 6490 N is...Ch. 11 - CP A uniform drawbridge must be held at a 37 angle...Ch. 11 - BIO Tendon-Stretching Exercises. As part of an...Ch. 11 - (a) In Fig. P11.60 a 6.00-m-loog, uniform beam is...Ch. 11 - A uniform, horizontal flagpole 5.00 m long with a...Ch. 11 - A holiday decoration consists of two shiny glass...Ch. 11 - BIO Downward-Facing Dog. The yoga exercise...Ch. 11 - A uniform metal bar that is 8.00 m long and has...Ch. 11 - A worker wants to turn over a uniform. 1250-N,...Ch. 11 - One end of a uniform meter stick is placed against...Ch. 11 - Two friends are carrying a 200-kg crate up a...Ch. 11 - BIO Forearm. In the human arm, the forearm and...Ch. 11 - BIO CALC Refer to the discussion of holding a...Ch. 11 - In a city park a nonuniform wooden beam 4.00 m...Ch. 11 - You are a summer intern for an architectural firm....Ch. 11 - You are trying to raise a bicycle wheel of mass m...Ch. 11 - The Farmyard Gate. A gate 4.00 m wide and 2.00 m...Ch. 11 - If you put a uniform block at the edge of a table,...Ch. 11 - Two uniform, 75.0-g marbles 2.00 cm in diameter...Ch. 11 - Two identical, uniform beams weighing 260 N each...Ch. 11 - An engineer is designing a conveyor system for...Ch. 11 - A weight W is supported by attaching it to a...Ch. 11 - A garage door is mounted on an overhead rail (Fig....Ch. 11 - Pyramid Guilders. Ancient pyramid builders are...Ch. 11 - CP A 12.0-kg mass, fastened to the end of an...Ch. 11 - Hookes Law for a Wire. 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