College Physics
2nd Edition
ISBN: 9780134601823
Author: ETKINA, Eugenia, Planinšič, G. (gorazd), Van Heuvelen, Alan
Publisher: Pearson,
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Textbook Question
Chapter 21, Problem 4P
* Flashlight without batteries A flashlight that operates without batteries is lying on your desk. The light illuminates only when you repeatedly squeeze the flashlight’s handle. You notice that paper clips tend to stick to the outside of the flashlight. What physical mechanism might control the operation of the flashlight?
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Chapter 21 Solutions
College Physics
Ch. 21 - Review Question 21.1 Your friend thinks that...Ch. 21 - Review Question 21.2 You have a bar magnet and a...Ch. 21 - Review Question 21.3 What difficulty would occur...Ch. 21 - Review Question 21.4 Why do we write the law of...Ch. 21 - Review Question 21.5 How does the law of...Ch. 21 - Review Question 21.6 A capacitor in an electric...Ch. 21 - Prob. 7RQCh. 21 - Review Question 21.8 Explain how (a) an electric...Ch. 21 - 1. In which of the experiments with a loop and a...Ch. 21 - If you move the coil in Figure Q21.2 toward the N...
Ch. 21 - The magnetic flux through a 100-cm2 loop is...Ch. 21 - Your friend says that the emf induced in a coil...Ch. 21 - 5. A metal ring lies on a table. The S pole of a...Ch. 21 - 6. One coil is placed on lop of another The bottom...Ch. 21 - Two coils are placed next to each other flat on...Ch. 21 - 8. Two identical bar magnets are dropped...Ch. 21 - A windows metal frame is essentially a metal loop...Ch. 21 - Four identical loops move at the same velocity...Ch. 21 - A 12-V automobile battery provides the thousands...Ch. 21 - A respiration detector consists of a coil placed...Ch. 21 - A parallel plate capacitor and a lightbulb are...Ch. 21 - Prob. 14MCQCh. 21 - A bar magnet falling with the north pole facing...Ch. 21 - 16. An induction cooktop has a smooth surface When...Ch. 21 - Describe three common applications of...Ch. 21 - 18. Two rectangular loops A and B are near each...Ch. 21 - A simple metal detector has a coil with an...Ch. 21 - 20. Construct flux-versus-time and emf-versus-time...Ch. 21 - How is it possible to get a 2000-V emf from a...Ch. 21 - You connect a capacitor and a lightbulb in series...Ch. 21 - Prob. 23CQCh. 21 - * You and your friend are performing experiments...Ch. 21 - You decide to use a metal ring as an indicator of...Ch. 21 - * To check whether a lightbulb permanently...Ch. 21 - * Flashlight without batteries A flashlight that...Ch. 21 - You need to invent a practical application for a...Ch. 21 - * Detect burglars entering windows. Describe how...Ch. 21 - 7. * A coil connected to an ammeter can detect...Ch. 21 - * The B field in a region has a magnitude of 0.40...Ch. 21 - 9. EST How do you position a bicycle tire so that...Ch. 21 - * EST Estimate the magnetic flux through your head...Ch. 21 - 11. * Estimate the magnetic flux through the...Ch. 21 - Prob. 12PCh. 21 - 13. You have the apparatus shown in Figure P21.13....Ch. 21 - * You suggest that eddy currents can stop the...Ch. 21 - * Your friend thinks that an induced magnetic...Ch. 21 - The magnetic flux through three different coils is...Ch. 21 - 17. The magnetic flux through three different...Ch. 21 - 18. A magnetic field passing through two coils of...Ch. 21 - BIO Stimulating the brain in transcranial magnetic...Ch. 21 - * To measure a magnetic field produced by an...Ch. 21 - Prob. 21PCh. 21 - 22 * BIO Breathing monitor An apnea monitor for...Ch. 21 - 23. * A bar magnet induces a current in an -turn...Ch. 21 - * An experimental apparatus has two parallel...Ch. 21 - A Boeing 747 with a 65-m wingspan is cruising...Ch. 21 - Prob. 27PCh. 21 - 28. ** BIO EST Magnetic field and brain cells...Ch. 21 - * You need to test Faraday's law You have a...Ch. 21 - 30. * You build a coil of radius r (m) and place...Ch. 21 - * EST Generator for space station Astronauts on a...Ch. 21 - 35. * A toy electric generator has a 20-tum...Ch. 21 - 36. * A generator has a 450-turn coil that is 10...Ch. 21 - 39. * A generator has a 100-turn coil that rotates...Ch. 21 - Prob. 40PCh. 21 - * A rectangular wire loop is moving with constant...Ch. 21 - field that points into the page (Figure P21.42)....Ch. 21 - 43. The voltage across an AC power supply is given...Ch. 21 - 44. * The alternating current through a capacitor...Ch. 21 - * The alternating current through a solenoid is...Ch. 21 - 46. * The rms voltage of household AC in Europe is...Ch. 21 - Prob. 47PCh. 21 - Prob. 48PCh. 21 - 49. You need to build a transformer that can step...Ch. 21 - 50. Your home’s electric doorbell operates on 10...Ch. 21 - 51. A 9.0-V battery and switch are connected in...Ch. 21 - * You are fixing a transformer for a toy truck...Ch. 21 - 53. * A wire loop has a radius of 10 cm. A...Ch. 21 - BIO Hammerhead shark A hammerhead shark (Figure...Ch. 21 - ** You have a 12-V battery, some wire, a switch,...Ch. 21 - 61.* EST A sparker used to ignite lighter fluid in...Ch. 21 - * EST Design a magnetometer Your friend needs to...Ch. 21 - Prob. 63GPCh. 21 - 64 EST MRI Jose needs an MRI (magnetic resonance...Ch. 21 - * Magstripe reader A magstripe reader used to read...Ch. 21 - 66. Show that when a metal rod L meters long moves...Ch. 21 - 67. ** EST The Tower of Terror ride Magnetic...Ch. 21 - BIO Magnetic induction tomography (MIT) Magnetic...Ch. 21 - BIO Magnetic induction tomography (MIT) Magnetic...Ch. 21 - BIO Magnetic induction tomography (MIT) Magnetic...Ch. 21 - BIO Magnetic induction tomography (MIT) Magnetic...Ch. 21 - BIO Magnetic induction tomography (MIT) Magnetic...Ch. 21 - BIO Magnetic induction tomography (MIT) Magnetic...Ch. 21 - BIO Magnetic induction tomography (MIT) Magnetic...Ch. 21 - BIO Magnetic induction tomography (MIT) Magnetic...Ch. 21 - BIO Magnetic induction tomography (MIT) Magnetic...
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