In the figure, a wire shaped like a circular loop of radius r =15.0 cm is stretched by pulling on its sides so that the area in the loop decreases to zero in 0.250 s. This is done in the presence of a 0.800-T magnetic field that comes out of the page, as shown in the figure. What is the magnitude of the induced EMF and the direction of the current induced in the loop as it's being stretched? A)

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A circular loop in the plane of a paper lies in a 0.65 T magnetic field pointing into the paper. The loop's diameter changes from 19.5 cm to 5.4 cm in 0.55 s. 1) What is the direction of the induced current? 2) What is the magnitude of the average induced emf? 3) What is the average induced current if the coil resistance is 4.7 Ω ?

A circular loop in the plane of a paper lies in a 0.65 T magnetic field pointing into the paper. The loop's diameter changes from 21.5 cm to 6.8 cm in 0.52 s . What is the magnitude of the average induced emf?

An electromagnet is turned on to produce a magnetic field that stabilizes at 3 T after 0.5 s. A single wire loop of radius 0.1 m is aligned perpendicular to the magnetic field. What is the average emf produced in the wire loop over the time it takes the current to stabilize

Suppose a magnetic field B(t) oscillates with frequency w. A circular loop of copper lies perpendicular to the magnetic field. The radius of the circular loop is r. a. Write down an expression for the magnetic field as a function of time. Determine the induced emf & in the loop of wire and use this to calculate the current generated in the loop as a function of time. b. What is the power dissipation in the wire as a function to time? Make a sketch of this function. What is the average power Pave dissipation in the wire? Hint: what is the average value of the function you sketched? C. Recall that power is a rate of energy transfer, and that power dissipated by a resistor leads to a change in the thermal energy of the material (in this case the copper wire). We can relate a change in thermal energy to a change in temperature by AT where M is the total mass and c ΔΕth Mc is the specific heat capacity of the material (see page 526 for details). Find an expression for a dT - differential…

A metal rod 0.84 m long moves with a speed of 1.9 m/s perpendicular to a magnetic field. If the induced emf between the ends of the rod is 0.39 V , what is the strength of the magnetic field? Express your answer using two significant figures.

A square coil of wire has 10 turns and an area of 20 cm^2. The square coil is located in a variable magnetic field whose behavior is shown on the graph.  The magnetic field is directed at an angle of 45° relative to the normal to the plane of the square coil.    a. What is the average emf induced in the coil in the time interval from t=7.50 s to 10.0 s?     b. If the wire has a resistance of 0.75 Ω determine the induced current for the interval from part (a)?

A loop of area 225 cm2 has 24 turns of wire. It is in a magnetic field of strength 3.6 x 10-2 T. To begin with, its plane (face) is parallel to the magnetic field lines. In a time of 0.15 s it is rotated so that its plane is perpendicular to the magnetic field lines. What is the average emf induced in the loop during the one-quarter rotation?

The figure below displays a circular loop of conducting wire in a uniform magnetic field pointing into the page. The radius of the loop is 10.0 cm and the magnitude of the field is 0.160 T. You grab points A and B and pull them in opposite directions, stretching the loop until its area is nearly zero, taking a time of 0.170 s to do so. What is the magnitude of the average induced emf in the loop (in mV) during this time? * х * X x х A x * * x K mV X x * x. B * * *