Physics of Everyday Phenomena
9th Edition
ISBN: 9781259894008
Author: W. Thomas Griffith, Juliet Brosing Professor
Publisher: McGraw-Hill Education
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Chapter 14, Problem 29CQ
Under which conditions are inductive detectors more effective than simple timer systems—when the traffic is heavy in all directions at all times or when the traffic varies with time of day and other factors? Explain. (See everyday phenomenon box 14.2.)
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Chapter 14 Solutions
Physics of Everyday Phenomena
Ch. 14 - The north pole of a handheld bar magnet is brought...Ch. 14 - If the distance between the south poles of two...Ch. 14 - In what respects is the force between two magnetic...Ch. 14 - Is it possible for a bar magnet to have just one...Ch. 14 - Does a compass needle always point directly...Ch. 14 - If we regard the Earth as a magnet, does its...Ch. 14 - We visualized the magnetic field of the Earth by...Ch. 14 - A horizontal wire is oriented along a north-south...Ch. 14 - A horizontal wire is oriented along an east-west...Ch. 14 - Is the force exerted by one current-carrying wire...
Ch. 14 - A uniform magnetic field is directed horizontally...Ch. 14 - A positively charged particle is momentarily at...Ch. 14 - If a uniform magnetic field is directed...Ch. 14 - Why does the magnetic force on a current-carrying...Ch. 14 - If we look down at the top of a circular loop of...Ch. 14 - If we were to represent the current loop of...Ch. 14 - A current-carrying rectangular loop of wire is...Ch. 14 - If the rectangular loop of wire shown in question...Ch. 14 - Because the magnetic fields of a coil of wire and...Ch. 14 - In what respect is a simple ammeter designed to...Ch. 14 - Does an ac motor require a split-ring commutator...Ch. 14 - Which type of motor typically runs at a fixed...Ch. 14 - If Faraday wound enough turns of wire on the...Ch. 14 - Is a magnetic flux the same as a magnetic field?...Ch. 14 - A horizontal loop of wire has a magnetic field...Ch. 14 - Suppose the magnetic flux through a coil of wire...Ch. 14 - Two coils of wire are identical except that coil....Ch. 14 - Do the sensors that detect vehicles at stoplights...Ch. 14 - Under which conditions are inductive detectors...Ch. 14 - If the magnetic field produced by the magnets in a...Ch. 14 - Does a simple generator produce a steady direct...Ch. 14 - A simple generator and a simple electric motor...Ch. 14 - Can a transformer be used, as shown in the...Ch. 14 - By stepping up the voltage of an...Ch. 14 - Prob. 1ECh. 14 - Two long parallel wires, each carrying a current...Ch. 14 - Prob. 3ECh. 14 - Prob. 4ECh. 14 - A wire carries a current of 12 A. How much charge...Ch. 14 - A particle with a charge of 0.6 C is moving at...Ch. 14 - A straight segment of wire has a length of 12 cm...Ch. 14 - The magnetic force on a 60-cm straight segment of...Ch. 14 - A coil of wire with 150 turns has a...Ch. 14 - A loop of wire enclosing an area of 0.04 m2 has a...Ch. 14 - The magnetic flux through a coil of wire changes...Ch. 14 - A coil of wire with 120 turns and a...Ch. 14 - Prob. 13ECh. 14 - If 15 A of current are supplied to the primary...Ch. 14 - Prob. 15ECh. 14 - Prob. 16ECh. 14 - Two long parallel wires carry currents of 8 A and...Ch. 14 - A small metal ball with a charge of +0.08 C and a...Ch. 14 - A rectangular coil of wire has dimensions of 4 cm...Ch. 14 - Prob. 4SP
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