Exam 30: Induction and Inductance

The graph shows the magnitude B of a uniform magnetic field that is perpendicular to the plane of a conducting loop. Rank the five regions indicated on the graph according to the magnitude of the emf induced in the loop, from least to greatest.

Coils P and Q each have a large number of turns of insulated wire. When switch S is closed, the pointer of galvanometer G is deflected toward the left. With S now closed, to make the pointer of G deflect toward the right one could:

A cylindrical region of radius R contains a uniform magnetic field parallel to its axis. The field is zero outside the cylinder. If the magnitude of the field is changing at the rate dB/dt, the electric field induced at a point 2R from the cylinder axis is:

A 10-turn ideal solenoid has an inductance of 4.0 mH. To generate an emf of 2.0 V the current should change at a rate of:

A rod with resistance R lies across frictionless conducting rails in a constant uniform magnetic field B, as shown. Assume the rails have negligible resistance. The magnitude of the force that must be applied by a person to pull the rod to the right at constant speed v is:

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

A 10 turn conducting loop with a radius of 3.0 cm spins at 60 revolutions per second in a magnetic field of 0.50 T. The maximum emf generated is:

The stored energy in an inductor:

The diagram shows a circular loop of wire that rotates at a steady rate about a diameter O that is perpendicular to a uniform magnetic field. The maximum induced emf occurs when the point X on the loop passes:

A single loop of wire with a radius of 7.5 cm rotates about a diameter in a uniform magnetic field of 1.6 T. To produce a maximum emf of 1.0 V, it should rotate at:

When the switch S in the circuit shown is closed, the time constant for the growth of current in R₂ is:

An inductor with inductance L restistor with resistance R are wired in series to an ideal battery with emf $\varepsilon$ . A switch in the circuit is closed at time 0, at which time the current is zero. A long time after the switch is thrown the potential differences across the inductor and resistor:

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

A cylindrical region of radius R = 3.0 cm contains a uniform magnetic field parallel to its axis. If the electric field induced at a point R/2 from the cylinder axis 4.5 *10^-3 v/m the magitude of the magnetic field must be changing at the rate:

A flat coil of wire, having 5 turns, has an inductance L. The inductance of a similar coil having 20 turns is:

A 6.0 mH inductor is in a series circuit with a resistor and an ideal battery. At the instant the current in the circuit is 5.0 A the energy stored in the inductor is:

A rectangular loop of wire is placed midway between two long straight parallel conductors as shown. The conductors carry currents i₁ and i₂ as indicated. If i₁ is increasing and i₂ is constant, then the induced current in the loop 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 rectangle is:

A 6.0-mH inductor and a 3.0- $\Omega$ resistor are wired in series to a 12-V ideal battery. A switch in the circuit is closed at time 0, at which time the current is zero. 2.0 ms later the energy stored in the inductor is:

A copper hoop is held in a vertical east-west plane in a uniform magnetic field whose field lines run along the north-south direction. The largest induced emf is produced when the hoop is: