University Physics (14th Edition)
14th Edition
ISBN: 9780133969290
Author: Hugh D. Young, Roger A. Freedman
Publisher: PEARSON
expand_more
expand_more
format_list_bulleted
Concept explainers
Videos
Textbook Question
Chapter 11, Problem 11.69P
BIO CALC Refer to the discussion of holding a dumbbell in Example 11.4 (Section 11.3). The maximum weight that can be held in this way is limited by the maximum allowable tendon tension T (determined by the strength of the tendons) and by the distance D from the elbow to where the tendon attaches to the forearm, (a) Let Tmax represent the maximum value of the tendon tension. Use the results of Example 11.4 to express wmax (the maximum weight that can be held) in terms of Tmax, L, D, and h. Your expression should not include the angle θ. (b) The tendons of different primates are attached to the forearm at different values of D. Calculate the derivative of wmax with respect to D, and determine whether the derivative is positive or negative, (c) A chimpanzee tendon is attached to the forearm at a point farther from the elbow than for humans. Use this to explain why chimpanzees have stronger arms than humans. (The disadvantage is that chimpanzees have less flexible arms than do humans.)
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
An individual leans forwards to pick up a box of 100 N. The weight of his upper body has a magnitude of 450 N. The back is pivoting around the base of the vertebral column. Consider the back of the individual as a rigid bar that is controlled by a muscle with an angle of 12° (See picture, d = trunk-head distance = 1 m).a) Calculate the magnitude of muscle force required to lift the box.b) Calculate the magnitude of the force at the base of the vertebral column. Hints: For (a) solve the equilibrium of moments, i.e. what force is required in the muscle to balance out the moments acting around the base of the spine.For (b), solve the equilibrium of forces acting on the spine, including the muscle force you’ve just calculated, in x and y separately. There are two extra forces not shown in the diagram: x and y contact forces acting at the base of the spine. These are whatever is needed to keep the total forces acting on the spine = 0 (so the spine isn’t accelerating off in some…
A tightrope walker stands on a wire that is supported by a pole at each end. The tightrope walker creates a tension of 3.42 ✕ 103 N in a wire making an angle 6.2° below the horizontal with each supporting pole. Calculate how much this tension stretches the steel wire (in cm) if it was originally 16 m long and 0.50 cm in diameter.
There is no accompanying image. This is the complete question.
In an emergency situation, a person with a broken forearm ties a strap from his hand to clip on his shoulder as in the figure below. His 1.60-kg forearm remains in a horizontal position and the
strap makes an angle of 0 = 53.5° with the horizontal. Assume the forearm is uniform, has a length of e = 0.324 m, assume the biceps muscle is relaxed, and ignore the mass and length of the
hand.
R
(a) Find the tension in the strap.
(b) Find the components of the reaction force exerted by the humerus on the forearm. (Assume the positive x-direction is to the right and the positive y-direction is upward.)
Ry =
N
R, =
N
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. Two forces equal in magnitude and...Ch. 11 - BIO A Good Workout. You are doing exercises on a...Ch. 11 - BIO Neck Muscles. A student bends her head at 40.0...Ch. 11 - BIO Biceps Muscle. A relaxed biceps muscle...Ch. 11 - A circular steel wire 2.00 m long must stretch no...Ch. 11 - Two circular rods, one steel and the other copper,...Ch. 11 - A metal rod that is 4.00 m long and 0.50 cm2 in...Ch. 11 - Stress on a Mountaineers Rope. A nylon rope used...Ch. 11 - In constructing a large mobile, an artist hangs an...Ch. 11 - A vertical, solid steel post 25 cm in diameter and...Ch. 11 - BIO Compression of Human Bone. The bulk modulus...Ch. 11 - A solid gold bar is pulled up from the hold of the...Ch. 11 - A specimen of oil having an initial volume of 600...Ch. 11 - In the Challenger Deep of the Marianas Trench, the...Ch. 11 - A copper cube measures 6.00 cm on each side. 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. A wire of length l0 and...Ch. 11 - A 1.05-m-long rod of negligible weight is...Ch. 11 - CP An amusement park ride consists of...Ch. 11 - CP BIO Stress on the Shin Bone. The compressive...Ch. 11 - DATA You are to use a long, thin wire to build a...Ch. 11 - Prob. 11.87PCh. 11 - DATA You are a construction engineer working on...Ch. 11 - Two ladders, 4.00 m and 3.00 m long, are hinged at...Ch. 11 - Knocking Over a Post. One end of a post weighing...Ch. 11 - CP An angler hangs a 4.50-kg fish from a vertical...Ch. 11 - BIO TORQUES AND TUG-OF-WAR. In a study of the...Ch. 11 - If he leans slightly farther back (increasing the...Ch. 11 - BIO TORQUES AND TUG-OF-WAR. In a study of the...Ch. 11 - BIO TORQUES AND TUG-OF-WAR. In a study of the...
Additional Science Textbook Solutions
Find more solutions based on key concepts
Express the unit vectors in terms of (that is, derive Eq. 1.64). Check your answers several ways Also work o...
Introduction to Electrodynamics
The maximum charge that is stored in the capacitor.
Physics (5th Edition)
The specific heat capacity of Albertsons Rotini Tricolore is approximately 1.8J/gC. Suppose you toss 340 g of t...
An Introduction to Thermal Physics
Due to the light absorbed by Earth’s surface that was emitted by Earth’s atmosphere, is Earth’s temperature nea...
Lecture- Tutorials for Introductory Astronomy
22. (a) Calculate the magnitude of the angular momentum of the earth in a circular orbit around the sun. Is it ...
College Physics (10th Edition)
The pV-diagram of the Carnot cycle.
Sears And Zemansky's University Physics With Modern Physics
Knowledge Booster
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, physics and related others by exploring similar questions and additional content below.Similar questions
- A 5.45-N beam of uniform density is 1.60 m long. The beam is supported at an angle of 35.0 by a cable attached to one end. There is a pin through the other end of the beam (Fig. P14.30). Use the values given in the figure to find the tension in the cable. FIGURE P14.30arrow_forwardRuby, with mass 55.0 kg, is trying to reach a box on a high shelf by standing on her tiptoes. In this position, half her weight is supported by the normal force exerted by the floor on the toes of each foot as shown in Figure P14.75A. This situation can be modeled mechanically by representing the force on Rubys Achilles tendon with FA and the force on her tibia as FT as shown in Figure P14.75B. What is the value of the angle and the magnitudes of the forces FA and FT? FIGURE P14.75arrow_forwardAn aluminium (=2.7g/cm3) wire is suspended from the ceiling and hangs vertically. How long must the wire be before the stress at its upper end reaches the proportionality limit, which is 8.0107N/m2 ?arrow_forward
- What Is Static Equilibrium? Problems 13 are grouped. 1. C A ball is attached to a strong, lightweight rod (Fig. P14.1). The rod is supported by a horizontal pin near the top. The ball is at rest. Is the ball in static equilibrium? If not, why not? If so, which type of equilibrium is itstable, unstable, or neutral? Hint: What would happen if you displaced the ball slightly? FIGURE P14.1arrow_forward12.9arrow_forwardIn the strict curl weightlifting event, a standing athlete lifts a barbell using only their lower arms, hinging at the elbow. The record weight is 900N. The biceps tendon connects 4.00cm from the elbow and pulls straight up, while the barbell is held 35.0cm from the elbow. Assume the weight of the forearm is negligible, and that each arm supports half the weight of the barbell. A) What is the tension in the tendon connecting the bicep to the forearm while held stationary in the position shown? B) What is the force (magnitude and direction) of the upp arm pushing on the forearm at the elbow joint?arrow_forward
- In exercise physiology it is sometimes important to determine the location of a person's center of gravity with respect to the plantar area. This can be done with the arrangement shown in the figure. A lightweight plank is supported by two scales that indicate Fg1 = 380.0 N and Fg2 = 320.0 N. The scales are separated by a distance of 2.00 m. At what distance from the woman's feet is her center of gravity? If a) the weight of the plank is neglected. b) if the plank has a weight of 55.0 N.arrow_forwardProblem 8: Consider a rigid steel beam of length L = 11.5 m and mass mb = 412 kg resting on two supports, one at each end. A worker of mass mw = 78 kg sits on the beam at a distance x from support A. Refer to the figure, though note that it is not drawn to scale. Part (a) When the worker sits at a distance x = 4.5 m from support A, calculate the force, in newtons, that support B must exert on the beam in order for it to remain at rest. Use g with three significant figures. Part (b) The force exerted on the beam by support A is measured and found to be FA = 2180 N. At what distance x, in meters, from support A is the worker sitting now?arrow_forward11.13 Find the 。 sion direction of the force exerted on the strut by the pivot in each of the arrangements in Fig. E11.13. In each case let w be the weight of the suspended crate full of priceless art objects. The strut is uni- form and also has weight w. Start each case with a free-body dia- gram of the strut. Figure E11.13 (a) (b) 30.0⁰ 45.0° 30.0°arrow_forward
- A 72.0-kg weightlifter doing arm raises holds a 7.50-kg weight. Her arm pivots around the elbow joint, starting 40.0° below the horizontal (Fig. P11.54). Biometric measurements have shown that, together, the forearms and the hands account for 6.00% of a person’s weight. Since the upper arm is held vertically, the biceps muscle always acts verti-cally and is attached to the bones of the forearm 5.50 cm from the elbow joint. The center of mass of this person’s forearm–hand combination is 16.0 cm from the elbow joint, along the bones of the forearm, and she holds the weight 38.0 cm from her elbow joint. (a) Draw a free-body diagram of the forearm. (b) What force does the biceps muscle exert on the forearm? (c) Find the magni-tude and direction of the force that the elbow joint exerts on the forearm. (d) As the weightlifter raises her arm toward a horizontal position, will the force in the biceps muscle increase, decrease, or stay the same? Why? Solve A B C D and show complete solutionarrow_forwardOne end of a uniform ℓ = 4.70-m-long rod of weight w is supported by a cable at an angle of ? = 37° with the rod. The other end rests against a wall, where it is held by friction (see figure). The coefficient of static friction between the wall and the rod is ?s = 0.520. Determine the minimum distance x from point A at which an additional weight w (the same as the weight of the rod) can be hung without causing the rod to slip at point A.arrow_forwardOne end of a uniform ℓ = 4.40-m-long rod of weight w is supported by a cable at an angle of ? = 37° with the rod. The other end rests against a wall, where it is held by friction (see figure). The coefficient of static friction between the wall and the rod is ?s = 0.570. Determine the minimum distance x from point A at which an additional weight w (the same as the weight of the rod) can be hung without causing the rod to slip at point A._______________________ marrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Physics for Scientists and Engineers: Foundations...PhysicsISBN:9781133939146Author:Katz, Debora M.Publisher:Cengage Learning
Principles of Physics: A Calculus-Based TextPhysicsISBN:9781133104261Author:Raymond A. Serway, John W. JewettPublisher:Cengage Learning
University Physics Volume 1PhysicsISBN:9781938168277Author:William Moebs, Samuel J. Ling, Jeff SannyPublisher:OpenStax - Rice University
Physics for Scientists and Engineers: Foundations...
Physics
ISBN:9781133939146
Author:Katz, Debora M.
Publisher:Cengage Learning
Principles of Physics: A Calculus-Based Text
Physics
ISBN:9781133104261
Author:Raymond A. Serway, John W. Jewett
Publisher:Cengage Learning
University Physics Volume 1
Physics
ISBN:9781938168277
Author:William Moebs, Samuel J. Ling, Jeff Sanny
Publisher:OpenStax - Rice University
Static Equilibrium: concept; Author: Jennifer Cash;https://www.youtube.com/watch?v=0BIgFKVnlBU;License: Standard YouTube License, CC-BY