A 109  turn circular coil of radius  2.41  cm is immersed in a uniform magnetic field that is perpendicular to the plane of the coil. Over an interval of  0.159  s , the magnetic field strength increases from 58.3  mT to  98.3  mT . Find the magnitude of the average emf  induced in the coil during this time interval, in millivolts.

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The maximum torque on a current carrying loop occurs when the angle between the loop’s magnetic moment and the magnetic field vector is 

A thin copper rod 1.0 m long has a mass of 0.050 kg and is in a magnetic field of 0.10 T. What minimum current in the rod is needed in order for the magnetic force to balance the weight of the rod?

The earth’s northern magnetic pole acts like

A positive ion of mass [m] x 10-25 kg enters perpendicular to a magnetic field of [B] T. The ion was initially accelerated by a potential difference of [V] volts. Calculate the radius of the path of the ion in the magnetic field.

An electron, moving west, enters a magnetic field of a certain strength. Because of this field the electron curves upward. What is the direction of the magnetic field?

An iron ring lies in a magnetic field as shown in the diagram. The field is uniformly increasing in magnitude. The induced current in the ring isScreen Shot 2021-07-29 at 3.16.27 PM.png 

How much current must pass through a 400-turn ideal solenoid that is 4.0 cm long to generate a 1.0-T magnetic field at the center? ( μ 0 = 4π × 10 -7 T ∙ m/A)

A simple ac circuit is composed of a capacitor connected across the terminals of an ac power source. If the frequency of the source is doubled, what happens to the reactance of the capacitor?