1. Two horizontal wires are kept in parallel at a distance of 0.2 cm apart a vertical plane. Both wires have equal currents in the same direction. the lower wire has a mass of 0.05 kg/m. if the lower wire appears to be weightless, what is the current in each wire? 2. Calculate the emf induced in a 2m long straight conductor when it is moved at a velocity of a 4 m/s across a magnetic field of 1.2 mWb/m2 at an angle of 60.?

1. Two horizontal wires are kept in parallel at a distance of 0.2 cm apart a vertical plane. Both wires have equal currents in the same direction. the lower wire has a mass of 0.05 kg/m. if the lower wire appears to be weightless, what is the current in each wire? 2. Calculate the emf induced in a 2m long straight conductor when it is moved at a velocity of a 4 m/s across a magnetic field of 1.2 mWb/m2 at an angle of 60.?

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter13: Electromagnetic Induction

Section: Chapter Questions

Problem 21CQ: A conducting sheet lies in a plane perpendicular to a magnetic field B that is below the sheet. If B...

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(a) An oxygen16 ion with a mass at 2.661026kg travels at 5.00106m/s perpendicular to a 1.20T magnetic field, which makes it move in a circular arc with a 0.231-m radius. What positive charge is on the ion? (b) What is the radio of this charge to the charge of an electron? (c) Discuss why the radio found in (b) should be an integer.
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Unreasonable results To construct a non-mechanical water meter, a 0.500-T magnetic field is placed across the supply water pipe to a home and the Hall voltage is recorded, (a) Find the flow rate through a 3.00-cm-diameter pipe if the Hall voltage is 60.0 mV. (b) What would the Hail voltage be for the same flow rate through a 10,0-cm- diameter pipe with tire same field applied?
Consider the system pictured in Figure P28.26. A 15.0-cm horizontal wire of mass 15.0 g is placed between two thin, vertical conductors, and a uniform magnetic field acts perpendicular to the page. The wire is free to move vertically without friction on the two vertical conductors. When a 5.00-A current is directed as shown in the figure, the horizontal wire moves upward at constant velocity in the presence of gravity. (a) What forces act on the horizontal wire, and (b) under what condition is the wire able to move upward at constant velocity? (c) Find the magnitude and direction of the minimum magnetic Field required to move the wire at constant speed. (d) What happens if the magnetic field exceeds this minimum value? Figure P28.26
(a) An MRI technician moves his hand from a region of very low magnetic field strength into an MRI scanner's 2.00 T field with his fingers pointing in the direction of the field. Find the average emf induced in his wedding ling, given its diameter is 2.20 cm and assuming it takes 0.250 s to move it into the field. (b) Discuss whether this current would significantly change the temperature of the ring.
Unreasonable results Frustrated by the small Hall voltage obtained in blood flow measurements, a medical physicist decides to increase the applied magnetic field strength to get a 0.500-V output for blood moving at 30.0 cm/s in a 1.50-cm-diameter vessel. (a) What magnetic field strength is needed? (b) What is unreasonable about this result? (C) Which premise is responsible?
Unreasonable Results Frustrated by the small Hall voltage obtained in blood flow measurements, a medical physicist decides to increase the applied magnetic field strength to get a 0.500V output for blood moving at 30.0 cm/s in a 1.50cmdiameter vessel. (a) What magnetic field strength is needed? (b) What is unreasonable about this result? (c) Which premise is responsible?
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An astronaut is connected to her spacecraft by a 25-m-long tether cord as she and the spacecraft orbit Earth in a circular path at a speed of 3.0 105 m/s. At one instant, the voltage measured between the ends of a wire embedded in the cord is measured to be 0.45 V. Assume the long dimension of the cord is perpendicular to the vertical component of Earths magnetic field at that instant. (a) What is the magnitude of the vertical component of Earths field at this location? (b) Does the measured voltage change as the system moves from one location to another? Explain.