Mastering Physics Solutions: Understanding Changing Flux

Mastering Physics Solutions: Understanding Changing Flux

On March 6, 2013, in Chapter 20: Electromagnetic Induction and Waves, by Mastering Physics Solutions

Part A = There is no magnetic flux through the wire loop.
Part B = There is no induced current.
Part C = The induced current is counterclockwise.
Part D = B, B

When the switch is open, which of the following statements about the magnetic flux through the wire loop is true? Assume that the direction of the vector area of the wire loop is to the right.
What is the direction of the induced current in the wire loop (as seen from the left) when the switch is open?
Now the switch on the electromagnet is closed. What is the direction of the induced current in the wire loop immediately after the switch is closed (as seen from the left)?
Finally, the switch on the electromagnet is reopened. The magnitude of the external magnetic flux through the wire loop ______ (A. increases, B. decreases, C. remains constant), and there is _______ (A. zero, B. a clockwise, C. a counterclockwise) current induced in the loop (as seen from the left).

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Mastering Physics Solutions: A Wire and a Compass

Mastering Physics Solutions: A Wire and a Compass

On March 6, 2013, in Chapter 19: Magnetism, by Mastering Physics Solutions

Part A = It is smaller
Part B = It is larger

If the wire is lowered farther from the compass, how does the new angle of deflection of the north pole of the compass needle compare to its initial deflection?
With the wire back at its initial location, you connect a second identical battery in series with the first one. When you close the switch, how does the new angle of deflection of the north pole of the compass needle compare to its initial deflection?

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Mastering Physics Solutions: Magnetic Force on a Bent Wire Conceptual Question

Mastering Physics Solutions: Magnetic Force on a Bent Wire Conceptual Question

On March 3, 2013, in Chapter 19: Magnetism, by Mastering Physics Solutions

Part A = +y
Part B = 0
Part C = +x
Part D = -y
Part E = 0
Part F = -y
Part G = -x

The bent wire circuit shown in the figure is in a region of space with a uniform magnetic field in the +z direction.
Determine the direction of the magnetic force along segment 1, which carries current in the -x direction.
Determine the direction of the magnetic force along segment 2, which carries current in the -z direction.
etc.

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Mastering Physics Solutions: Current Sheet

Mastering Physics Solutions: Current Sheet

On February 23, 2013, in Chapter 19: Magnetism, by Mastering Physics Solutions

Part A = See the screenshot

Consider an infinite sheet of parallel wires. The sheet lies in the xy plane. A current l runs in the -y direction through each wire. There are N/a wires per unit length in the x direction.

Write an expression for B(d),the magnetic field a distance d above the xy plane of the sheet.

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Mastering Physics Solutions: Exercise 20.6

Mastering Physics Solutions: Exercise 20.6

On May 25, 2012, in Chapter 20: Electromagnetic Induction and Waves, by Mastering Physics Solutions

Part A = 0.33 m2 Click to use the calculator/solver for this part of the problem
Part B = 42 V Click to use the calculator/solver for this part of the problem
Part C = 83 V Click to use the calculator/solver for this part of the problem

A uniform magnetic field is at right angles to the plane of a wire loop. The field decreases by 0.25 T in 1.0*10^−3 s and the magnitude of the average emf induced in the loop is 83 V.

What is the area of the loop?
What would be the value of the average induced emf if the field change was the same but took twice as long to decrease?
What would be the value of the average induced emf if the field decrease was twice as much and it also took twice as long to change?

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Mastering Physics Solutions: Exercise 20.7

Mastering Physics Solutions: Exercise 20.7

On May 23, 2012, in Chapter 20: Electromagnetic Induction and Waves, by Mastering Physics Solutions

Part A = 1.7 V Click to use the calculator/solver for this part of the problem
Part B = 0.44 V Click to use the calculator/solver for this part of the problem

A square loop of wire with sides of length 40 cm is in a uniform magnetic field perpendicular to its area.
If the field’s strength is initially 120 mT and it decays to zero in 0.011 s, what is the magnitude of the average emf induced in the loop?
What would be the average emf if the sides of the loop were only 20 cm?

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