Physics for Scientists and Engineers: Foundations and Connections
15th Edition
ISBN: 9781305289963
Author: Debora M. Katz
Publisher: Cengage Custom Learning
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Chapter 14, Problem 4PQ
While working on homework together, your friend stands her pencil on its sharpened tip. You say, “Nice trick. How did you do it?” Why do you think some trick had to be involved? Would you ask the same question if the pencil were lying on its side or if the pencil were unsharpened?
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Chapter 14 Solutions
Physics for Scientists and Engineers: Foundations and Connections
Ch. 14.1 - A rubber duck floats in a bathtub. Imagine moving...Ch. 14.1 - Prob. 14.2CECh. 14.2 - CASE STUDY Hanging a Plane from a Single Point In...Ch. 14.2 - Prob. 14.4CECh. 14.4 - Imagine two vertical rods initially of equal...Ch. 14 - What Is Static Equilibrium? Problems 13 are...Ch. 14 - Prob. 2PQCh. 14 - Two identical balls are attached to a...Ch. 14 - While working on homework together, your friend...Ch. 14 - Consider the sketch of a portion of a...
Ch. 14 - Prob. 6PQCh. 14 - Prob. 7PQCh. 14 - Prob. 8PQCh. 14 - The keystone of an arch is the stone at the top...Ch. 14 - Prob. 10PQCh. 14 - Stand straight and comfortably with your feet...Ch. 14 - Prob. 12PQCh. 14 - Prob. 13PQCh. 14 - Prob. 14PQCh. 14 - Prob. 15PQCh. 14 - Prob. 16PQCh. 14 - Prob. 17PQCh. 14 - Prob. 18PQCh. 14 - Prob. 19PQCh. 14 - Prob. 20PQCh. 14 - Prob. 21PQCh. 14 - The inner planets of our solar system are...Ch. 14 - Two Boy Scouts, Bobby and Jimmy, are carrying a...Ch. 14 - Prob. 24PQCh. 14 - A painter of mass 87.8 kg is 1.45 m from the top...Ch. 14 - Consider the situation in Problem 25. Tests have...Ch. 14 - Children playing pirates have suspended a uniform...Ch. 14 - Prob. 28PQCh. 14 - Prob. 29PQCh. 14 - A 5.45-N beam of uniform density is 1.60 m long....Ch. 14 - A wooden door 2.1 m high and 0.90 m wide is hung...Ch. 14 - A 215-kg robotic arm at an assembly plant is...Ch. 14 - Problems 33 and 34 are paired. One end of a...Ch. 14 - For the uniform beam in Problem 33, find the...Ch. 14 - Prob. 35PQCh. 14 - A square plate with sides of length 4.0 m can...Ch. 14 - Prob. 37PQCh. 14 - At a museum, a 1300-kg model aircraft is hung from...Ch. 14 - A uniform wire (Y = 2.0 1011 N/m2) is subjected...Ch. 14 - A brass wire and a steel wire, both of the same...Ch. 14 - In Example 14.3, we found that one of the steel...Ch. 14 - A carbon nanotube is a nanometer-scale cylindrical...Ch. 14 - A nanotube with a Youngs modulus of 1.000 1012 Pa...Ch. 14 - Consider a nanotube with a Youngs modulus of 2.130...Ch. 14 - Prob. 45PQCh. 14 - Use the graph in Figure P14.46 to list the three...Ch. 14 - Prob. 47PQCh. 14 - A company is testing a new material made of...Ch. 14 - Prob. 49PQCh. 14 - Prob. 50PQCh. 14 - Prob. 51PQCh. 14 - Prob. 52PQCh. 14 - Prob. 53PQCh. 14 - Prob. 54PQCh. 14 - Prob. 55PQCh. 14 - Prob. 56PQCh. 14 - A copper rod with length 1.4 m and cross-sectional...Ch. 14 - Prob. 58PQCh. 14 - Prob. 59PQCh. 14 - Bruce Lee was famous for breaking concrete blocks...Ch. 14 - Prob. 61PQCh. 14 - Prob. 62PQCh. 14 - Prob. 63PQCh. 14 - A One end of a metal rod of weight Fg and length L...Ch. 14 - Prob. 65PQCh. 14 - A steel cable 2.00 m in length and with...Ch. 14 - Prob. 67PQCh. 14 - Prob. 68PQCh. 14 - Prob. 69PQCh. 14 - Prob. 70PQCh. 14 - Prob. 71PQCh. 14 - Prob. 72PQCh. 14 - Prob. 73PQCh. 14 - We know from studying friction forces that static...Ch. 14 - Ruby, with mass 55.0 kg, is trying to reach a box...Ch. 14 - An object is being weighed using an unequal-arm...Ch. 14 - Prob. 77PQCh. 14 - A massless, horizontal beam of length L and a...Ch. 14 - A rod of length 4.00 m with negligible mass is...Ch. 14 - A rod of length 4.00 m with negligible mass is...Ch. 14 - A horizontal, rigid bar of negligible weight is...Ch. 14 - Prob. 82PQCh. 14 - Prob. 83PQCh. 14 - Prob. 84PQCh. 14 - Prob. 85PQ
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- Figure P10.31 shows a claw hammer being used to pull a nail out of a horizontal board. The mass of the hammer is 1.00 kg. A force of 150 N is exerted horizontally as shown, and the nail does not yet move relative to the board. Find (a) the force exerted by the hammer claws on the nail and (b) the force exerted by the surface on the point of contact with the hammer head. Assume the force the hammer exerts on the nail is parallel to the nail. Figure P10.31arrow_forwardThe Iron Cross When a gymnast weighing 750 N executes the iron cross as in Figure lN.91a, the primary muscles involved in supporting this position are the latissimus dorsi (lats") and the pectoralis major (pecs"). The rings exert an upward force on the aims and support the weight of the gymnast. The force exerted by the shoulder joint on the arm is labeled Fs, while the two muscles exert a total force Fw on the arm. Estimate the magnitude of the force Fw. Note that one ring supports half the weight of the gymnast, which is 375 N as indicated in Figure P8.91b. Assume that the force Fw acts at an angle of 45 below the horizontal at a distance of 4.0 cm from the shoulder joint In your estimate, take the distance from the shoulder joint to the hand to be L = 70 cm and ignore the weight of the arm.arrow_forwardA stick is resting on a concrete step with 29 of its total length ? hanging over the edge. A single ladybug lands on the end of the stick hanging over the edge, and the stick begins to tip. A moment later, a second, identical ladybug lands on the other end of the stick, which results in the stick coming momentarily to rest at ?=62.1∘ with respect to the horizontal, as shown in the figure. If the mass of each bug is 3.09 times the mass of the stick and the stick is 15.1 cm long, what is the magnitude ? of the angular acceleration of the stick at the instant shown? Use ?=9.81 m/s2.arrow_forward
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- In this experiment, if, say 20 kg are placed on the left side, can the plank be balanced with only 10 kg on the right side? Group of answer choices 1-Yes, if the 10 kg are as far from the fulcrum as the 20 kg. 2-Yes, if the 10 kg are placed half as far from the fulcrum as the 20 kg. 3-No, because then the sum of torques will not be zero 4-Yes, if the 10 kg are placed twice as far from the fulcrum as the 20 kg. 5-No, because then the sum of forces will not be zero One of the conditions for equilibrium is that the sum of torques must be zero. Suppose that the plank is in equilibrium with some weights on it. The torque about the fulcrum will be zero. Will the torque calculated about the left edge of the plank also be equal to zero? Group of answer choices 1-Yes 2-It may or may not be. 3-No Suppose that the plank has a mass 15 kg, and we place 10 kg on the left side at a distance 2.00 m from the fulcrum, and a mass 20 kg on the right side at a distance 1.00 m…arrow_forwardWhich identical board experiences the larger net torque around its marked axis?(the axes of rotation of A is exactly in the middle of the board) a) net torque on A is greaterb) net torque on B is greaterc) net torque on both are equalarrow_forwardthe bones of the forearm (radius and ulna) are hinged to the humerus at the elbow. The biceps muscle connects to the bones of the forearm about 2.152.15 cm beyond the joint. Assume the forearm has a mass of 2.152.15 kg and a length of 0.4050.405 m. When the humerus and the biceps are nearly vertical and the forearm is horizontal, if a person wishes to hold an object of mass 4.954.95 kg so that her forearm remains motionless, what is the force ?F exerted by the biceps muscle?arrow_forward
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