College Physics:
11th Edition
ISBN: 9781305965515
Author: SERWAY, Raymond A.
Publisher: Brooks/Cole Pub Co
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Textbook Question
Chapter 8, Problem 41P
An approximate model for a ceiling fan consists of a cylindrical disk with four thin rods extending from the disk’s center, as in Figure P8.41. The disk has mass 2.50 kg and radius 0.200 m. Each rod has mass 0.850 kg and is 0.750 m long, (a) Find the ceiling fan’s moment of inertia about a vertical axis through the disk’s center, (b) Friction exerts a constant torque of magnitude 0.115 N · m on the fan as it rotates. Find the magnitude of the constant torque provided by the fan’s motor if the fan starts from rest and takes 15.0 s and 18.5 full revolutions to reach its maximum speed.
Figure P8.41
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Chapter 8 Solutions
College Physics:
Ch. 8.4 - Using a screwdriver, you try to remove a screw...Ch. 8.4 - A constant net torque is applied to an object....Ch. 8.4 - The two rigid objects shown in Figure 8.21 have...Ch. 8.5 - Two spheres, one hollow and one solid, are...Ch. 8.6 - A horizontal disk with moment of inertia I1...Ch. 8.6 - If global warming continues, its likely that some...Ch. 8 - Why cant you put your heels firmly against a wall...Ch. 8 - Two point masses are the same distance R from an...Ch. 8 - If you see an object rotating, is there...Ch. 8 - (a) Is it possible to calculate the torque acting...
Ch. 8 - Why does a long pole help a tightrope walker stay...Ch. 8 - A person stands a distance R from a doors hinges...Ch. 8 - Orbiting spacecraft contain internal gyroscopes...Ch. 8 - If you toss a textbook into the air, rotating it...Ch. 8 - Stars originate as large bodies of slowly rotating...Ch. 8 - An object is acted on by a single nonzero force of...Ch. 8 - In a tape recorder, the tape is pulled past the...Ch. 8 - (a) Give an example in which the net force acting...Ch. 8 - Gravity is an example of a central force that acts...Ch. 8 - A cat usually lands on its feet regardless of the...Ch. 8 - A solid disk and a hoop are simultaneously...Ch. 8 - A mouse is initially at rest on a horizontal...Ch. 8 - The cars in a soapbox derby have no engines; they...Ch. 8 - A man opens a 1.00-m wide door by pushing on it...Ch. 8 - A worker applies a torque to a nut with a wrench...Ch. 8 - The fishing pole in Figure P8.3 makes an angle of...Ch. 8 - Find the net torque on the wheel in Figure P8.4...Ch. 8 - Figure P8.4 Calculate the net torque (magnitude...Ch. 8 - A dental bracket exerts a horizontal force of 80.0...Ch. 8 - A simple pendulum consists of a small object of...Ch. 8 - Prob. 8PCh. 8 - Prob. 9PCh. 8 - Prob. 10PCh. 8 - Prob. 11PCh. 8 - Prob. 12PCh. 8 - Prob. 13PCh. 8 - The Xanthar mothership locks onto an enemy cruiser...Ch. 8 - Prob. 15PCh. 8 - Prob. 16PCh. 8 - Torque and the Two Conditions for Equilibrium 17....Ch. 8 - Prob. 18PCh. 8 - A cook holds a 2.00-kg carton of milk at arm's...Ch. 8 - A meter stick is found to balance at the 49.7-cm...Ch. 8 - Prob. 21PCh. 8 - A beam resting on two pivots has a length of L =...Ch. 8 - Prob. 23PCh. 8 - When a person stands on tiptoe (a strenuous...Ch. 8 - A 500.-N uniform rectangular sign 4.00 m wide and...Ch. 8 - A window washer is standing on a scaffold...Ch. 8 - A uniform plank of length 2.00 m and mass 30.0 kg...Ch. 8 - A hungry bear weighing 700. N walks out on a beam...Ch. 8 - Prob. 29PCh. 8 - Prob. 30PCh. 8 - Prob. 31PCh. 8 - Write the necessary equations of equilibrium of...Ch. 8 - Prob. 33PCh. 8 - Prob. 34PCh. 8 - Prob. 35PCh. 8 - Prob. 36PCh. 8 - Four objects are held in position at the corners...Ch. 8 - If the system shown in Figure P8.37 is set in...Ch. 8 - A large grinding wheel in the shape of a solid...Ch. 8 - An oversized yo-yo is made from two identical...Ch. 8 - An approximate model for a ceiling fan consists of...Ch. 8 - A potters wheel having a radius of 0.50 m and a...Ch. 8 - A model airplane with mass 0.750 kg is tethered by...Ch. 8 - A bicycle wheel has a diameter of 64.0 cm and a...Ch. 8 - A 150.-kg merry-go-round in the shape of a...Ch. 8 - An Atwoods machine consists of blocks of masses m1...Ch. 8 - The uniform thin rod in Figure P8.47 has mass M =...Ch. 8 - A 2.50-kg solid, uniform disk rolls without...Ch. 8 - A horizontal 800.-N merry-go-round of radius 1.50...Ch. 8 - Four objectsa hoop, a solid cylinder, a solid...Ch. 8 - A light rod of length = 1.00 m rotates about an...Ch. 8 - A 240-N sphere 0.20 m in radius rolls without...Ch. 8 - A solid, uniform disk of radius 0.250 m and mass...Ch. 8 - A car is designed to get its energy from a...Ch. 8 - The top in Figure P8.55 has a moment of inertia of...Ch. 8 - A constant torque of 25.0 N m is applied to a...Ch. 8 - A 10.0-kg cylinder rolls without slipping on a...Ch. 8 - Use conservation of energy to determine the...Ch. 8 - A 2.00-kg solid, uniform ball of radius 0.100 m is...Ch. 8 - Each of the following objects has a radius of...Ch. 8 - A metal hoop lies on a horizontal table, free to...Ch. 8 - A disk of mass m is spinning freely at 6.00 rad/s...Ch. 8 - (a) Calculate the angular momentum of Earth that...Ch. 8 - A 0.005 00-kg bullet traveling horizontally with a...Ch. 8 - A light, rigid rod of length = 1.00 m rotates...Ch. 8 - Haileys comet moves about the Sun in an elliptical...Ch. 8 - A student holds a spinning bicycle wheel while...Ch. 8 - A 60.0-kg woman stands at the rim of a horizontal...Ch. 8 - A solid, horizontal cylinder of mass 10.0 kg and...Ch. 8 - A student sits on a rotating stool holding two...Ch. 8 - The puck in Figure P8.71 has a mass of 0.120 kg....Ch. 8 - A space station shaped like a giant wheel has a...Ch. 8 - A cylinder with moment of inertia I1 rotates with...Ch. 8 - A particle of mass 0.400 kg is attached to the...Ch. 8 - Additional Problems A typical propeller of a...Ch. 8 - Prob. 76APCh. 8 - Prob. 77APCh. 8 - Prob. 78APCh. 8 - A uniform ladder of length L and weight w is...Ch. 8 - Two astronauts (Fig. P8.80), each haring a mass of...Ch. 8 - S This is a symbolic version of problem 80. Two...Ch. 8 - Two window washers. Bob and Joe, are on a...Ch. 8 - A 2.35-kg uniform bar of length = 1.30 m is held...Ch. 8 - A light rod of length 2L is free to rotate in a...Ch. 8 - Prob. 85APCh. 8 - A uniform thin rod of length L and mass M is free...Ch. 8 - Prob. 87APCh. 8 - Prob. 88APCh. 8 - A war-wolf, or trebuchet, is a device used during...Ch. 8 - A string is wrapped around a uniform cylinder of...Ch. 8 - The Iron Cross When a gymnast weighing 750 N...Ch. 8 - In an emergency situation, a person with a broken...Ch. 8 - An object of mass m1 = 4.00 kg is connected by a...Ch. 8 - Prob. 94APCh. 8 - A 3.2-kg sphere is suspended by a cord that passes...
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