College Physics: A Strategic Approach (4th Edition)
4th Edition
ISBN: 9780134609034
Author: Randall D. Knight (Professor Emeritus), Brian Jones, Stuart Field
Publisher: PEARSON
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Textbook Question
Chapter 25, Problem 70GP
In reading the instruction manual that came with your garage- door opener, you sec that the transmitter unit in your car produces a 250 mW signal and that the receiver unit is supposed to respond to a radio wave of the cancel frequency if the electric field amplitude exceeds 0.10 V/m. You wonder if this is really true. To find out, you put fresh batteries in the transmitter and start walking away from your garage while opening and closing the door. Your garage door finally fails to respond when you’re 42 m away. Are the manufacturer’s claims true?
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In reading the instruction manual that came with your garage-door opener, you see that the transmitter unit in your car produces a 250 mW signal and that the receiver unit is supposed to respond to a radio wave of the correct frequency if the electric field amplitude exceeds 0.10 V/m. You wonder if this is really true. To find out, you put fresh batteries in the transmitter and start walking away from your garage while opening and closing the door. Your garage door finally fails to respond when you’re 42 m away. Are the manufacturer’s claims true?
Patients undergoing an MRI occasionally report
seeing flashes of light. Some practitioners assume
that this results from electric stimulation of the eye
by the emf induced by the rapidly changing fields of
an MRI solenoid. We can do a quick calculation to
see if this is a reasonable assumption. The human
eyeball has a diameter of approximately 25 mm.
Rapid changes in current in an MRI solenoid can
produce rapid changes in field, with AB/At as
large as 60 T/s.
For the steps and strategies involved in solving a
similar problem, you may view a
Video Tutor Solution.
loop circling the
Express your answer with the appropriate units.
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How does this compare to the 15 mV necessary to trigger an action potential?
This amount of emf is absolutely inadequate to trigger an action potential.
O
This amount of emf is almost adequate to trigger an action potential.
O
This amount of emf is inadequate to trigger an action potential.
O This…
Patients undergoing an MRI occasionally report seeing flashes of light. Some practitioners assume that this results from electric stimulation of the eye by the emf induced by the rapidly changing fields of an MRI solenoid. We can do a quick calculation to see if this is a reasonable assumption. The human eyeball has a diameter of approximately 25 mm. Rapid changes in current in an MRI solenoid can produce rapid changes in field, with ΔB/Δt as large as 50 T/s. What emf would this induce in a loop circling the eyeball? How does this compare to the 15 mV necessary to trigger an action potential?
Chapter 25 Solutions
College Physics: A Strategic Approach (4th Edition)
Ch. 25 - Prob. 1CQCh. 25 - Prob. 2CQCh. 25 - Prob. 3CQCh. 25 - Prob. 4CQCh. 25 - Prob. 5CQCh. 25 - Prob. 6CQCh. 25 - The power lines that run through your neighborhood...Ch. 25 - The magnetic flux passing through a coil of wire...Ch. 25 - There is a counterclockwise induced current in the...Ch. 25 - Prob. 10CQ
Ch. 25 - The conducting loop in Figure Q25.11 is moving...Ch. 25 - Figure Q25.12 shows two concentric, conducting...Ch. 25 - Figure Q25.13 shows conducting loops next to each...Ch. 25 - Prob. 15CQCh. 25 - Prob. 16CQCh. 25 - Prob. 17CQCh. 25 - A metal wire is resting on a U-shaped conducting...Ch. 25 - Prob. 19CQCh. 25 - Prob. 20CQCh. 25 - Prob. 21CQCh. 25 - Prob. 22CQCh. 25 - Prob. 23CQCh. 25 - Prob. 24CQCh. 25 - Arc welding uses electric current to make an...Ch. 25 - A circular loop of wire has an area of 0.30 m2. It...Ch. 25 - In Figure Q25.27, a square loop is rotating in the...Ch. 25 - A diamond-shaped loop of wire is pulled at a...Ch. 25 - Figure Q25.29 shows a triangular loop of wire in a...Ch. 25 - A device called a flip coil can be used to measure...Ch. 25 - The electromagnetic waves that carry FM radio...Ch. 25 - The beam from a laser is focused with a lens,...Ch. 25 - A spacecraft in orbit around the moon measures its...Ch. 25 - A 6.0 mW vertically polarized laser beam passes...Ch. 25 - Prob. 36MCQCh. 25 - Prob. 1PCh. 25 - Prob. 2PCh. 25 - A l0-cm-long wire is pulled along a U-shaped...Ch. 25 - Figure P25.4 shows a 15-cm-long metal rod pulled...Ch. 25 - Prob. 5PCh. 25 - In the rainy season, the Amazon flows fast and...Ch. 25 - A delivery truck with 2.8-m-high aluminum sides is...Ch. 25 - Prob. 8PCh. 25 - Prob. 9PCh. 25 - Prob. 10PCh. 25 - Prob. 11PCh. 25 - Prob. 12PCh. 25 - Prob. 13PCh. 25 - A magnet and a coil are oriented as shown in...Ch. 25 - A 1000-turn coil of wire 2.0 cm in diameter is in...Ch. 25 - Figure P25.I6 shows a 100-turn coil of wire of...Ch. 25 - Figure P25.17 shows a 10-cm-diameter loop in three...Ch. 25 - Prob. 18PCh. 25 - Prob. 19PCh. 25 - Prob. 20PCh. 25 - Prob. 21PCh. 25 - Prob. 22PCh. 25 - Prob. 23PCh. 25 - Prob. 24PCh. 25 - Prob. 25PCh. 25 - Prob. 26PCh. 25 - A microwave oven operates at 2.4 GHz with an...Ch. 25 - The maximum allowed leakage of microwave radiation...Ch. 25 - Prob. 29PCh. 25 - Prob. 30PCh. 25 - At what distance from a 10 mW point source of...Ch. 25 - Prob. 32PCh. 25 - A radio antenna broadcasts a 1.0 MHz radio wave...Ch. 25 - Prob. 34PCh. 25 - The intensity of a polarized electromagnetic wave...Ch. 25 - Prob. 36PCh. 25 - Prob. 37PCh. 25 - Prob. 39PCh. 25 - Prob. 40PCh. 25 - Prob. 41PCh. 25 - Prob. 42PCh. 25 - One recent study has shown that x rays with a...Ch. 25 - Prob. 44PCh. 25 - Prob. 45PCh. 25 - Prob. 47PCh. 25 - Prob. 48PCh. 25 - Prob. 49PCh. 25 - A particular species of copepod, a small marine...Ch. 25 - Prob. 51PCh. 25 - Prob. 52PCh. 25 - Prob. 53PCh. 25 - Prob. 54PCh. 25 - Prob. 55PCh. 25 - A python can detect thermal radiation with...Ch. 25 - If astronomers look toward any point in outer...Ch. 25 - Prob. 58GPCh. 25 - People immersed in strong unchanging magnetic...Ch. 25 - Prob. 60GPCh. 25 - Prob. 61GPCh. 25 - Prob. 62GPCh. 25 - A 20-cm-long, zero-resistance wire is pulled...Ch. 25 - A TMS (transeranial magnetic stimulation) device...Ch. 25 - The 10-cm-wide, zero-resistance wire shown in...Ch. 25 - Experiments to study vision often need to track...Ch. 25 - A LASIK vision correction system uses a laser that...Ch. 25 - A new cordless phone emits 4.0 mW at 5.8 GHz. The...Ch. 25 - In reading the instruction manual that came with...Ch. 25 - Unpolarized light passes through a vertical...Ch. 25 - Prob. 72GPCh. 25 - Prob. 73GPCh. 25 - Prob. 74GPCh. 25 - What is the wavelength of 27 MHz radio waves? A....Ch. 25 - If the frequency of the radio waves is increased,...Ch. 25 - Prob. 77MSPPCh. 25 - The metal detector will not detect insulators...Ch. 25 - A metal detector can detect the presence of metal...Ch. 25 - Which of the following changes would not produce a...
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- A 2.50-m-diameter university communications satellite dish receives TV signals that have a maximum electric field strength (for one channel) of 7.50 (V/m. (See Figure 24.28.) (a) What is the intensity of this wave? (b) What is the power received by the antenna? (c) If the orbiting satellite broadcasts uniformly over an area of 1.501013m2 (a large fraction of North America), how much power does it radiate? Figure 24.28 Satellite dishes receive TV signals sent from orbit. Although the signals are quite weak, the receiver can detect them by being tuned to resonate at their frequency.arrow_forwardUsing an electromagnetic flowmeter (Fig. P19.69), a heart surgeon monitors the flow rate of blood through an artery. Electrodes A and B make contact with the outer surface of the blood vessel, which has interior diameter 3.00 mm. (a) For a magnetic field magnitude of 0.040 0 T, a potential difference of 160 V appears between the electrodes. Calculate the speed of the blood. (b) Verify that electrode A is positive, as shown. Does the sign of the emf depend on whether the mobile ions in the blood are predominantly positively or negatively charged? Explain. Figure P19.69arrow_forwardIn what range of electromagnetic radiation are the electromagnetic waves emitted by power lines in a country that uses 50-Hz ac current?arrow_forward
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