Exam 30: Induction and Inductance

The normal to a certain 1.0 m² area makes an angle of 60 $\degree$ with a uniform magnetic field.The magnetic flux through this area is the same as the flux through a second area that is perpendicular to the field if the second area is:

A 10-turn ideal solenoid has an inductance of 3.5 mH.When the solenoid carries a current of 2.0 A the magnetic flux through each turn is:

A long straight wire is in the plane of a rectangular conducting loop.The straight wire carries an increasing current in the direction shown.The current in the loop is:

An inductance L, resistance R, and ideal battery of emf are wired in series.A switch in the circuit is closed at time t = 0, at which time the current is zero.At any later time t the emf of the inductor is given by:

A changing magnetic field pierces the interior of a circuit containing three identical resistors.Two voltmeters are connected as shown.V₁ reads 1 mV across R.V₂ reads the voltage across the other two resistors, which is:

A rectangular loop of wire is placed perpendicular to a uniform magnetic field and then spun around one of its sides at frequency f.The induced emf is a maximum when:

A vertical bar magnet is dropped through the center of a horizontal loop of wire, with its north pole leading.At the instant when the midpoint of the magnet is in the plane of the loop, the induced current in the loop, viewed from above, is:

Suppose this page is perpendicular to a uniform magnetic field and the magnetic flux through it is 5.0 Wb.If the page is turned by 30 $\degree$ around an edge the flux through it will be:

The units of motional emf are:

As a loop of wire with a resistance of 10 $\Omega$ moves in a constant non-uniform magnetic field, it loses kinetic energy at a uniform rate of 5.0 mJ/s.The induced current in the loop is: