Reading Quiz #9

1. What is the equivalent resistance of a series of resistors?

a) sum of the individual resistances

b) inverse of the sum of the inverse resistances

2) Which is NOT one of Kirchhoff’s rules for circuits?

a. Junction rule

b. Loop rule

c. Resistance rule

d. None of the above

Reading Quiz #10

1) What determines the time it takes to charge up a capacitor in an RC circuit?

a) Battery voltage and currentb) Battery voltage and resistancec) Current and capacitanced) Capacitance and resistancee) None of the above

2) What should be avoided to prevent electric shock?a) standing next to high voltageb) flow of current through body partsc) touching the ground wire d) All of the above

Reading Quiz #111) Magnetic field lines outside of a magnet run from

a) south to north poleb) north to south polec) there is no magnetic analog of electric field lines

2) The force of a magnet on a current-carrying wire isa) zerob) perpendicular to direction of the currentc) parallel to the direction of the current

3) The unit of the magnetic field is a) Oersted b) Farad c) Weber d) Tesla

Reading Quiz #121) Which is (are) true? The magnetic dipole moment of a

current loop a) Is prop. to the area of the loopb) Is prop. to the current in the loopc) Is well-defined only far away from the loopd) All of the abovee) Two of the above

2) The oil-drop experiment is used to a) Measure the mass of the electronb) Measure the charge of the electronc) Measure the ratio of charge and mass of the electrond) None of the above

Reading Quiz #13

1) The magnetic force between two wires is a) proportional to the distance d between them

b) proportional to 1/d

c) proportional to 1/d2

2) The force between two parallel currents (going in the same direction) is …

a. Zero

b. Repulsive

c. attractive

Reading Quiz #14

1) Ampere’s Law says that …a) the magnetic flux through an area is proportional to the current in a closed loopb) the integral of the magnetic field along a closed path is proportional to the current enclosed by the pathc) none of the above

2) In the modern definition, which is more fundamental, i.e. easier to measure?

a) Current measured in Amperesb) Charge measured in Coulombs

Reading Quiz #15

1) The Biot-Savart Law …a) Can be used to determine a B field of a currentb) Is the same as Ampere’s lawc) Is the same as Gauss’ lawd) None of the above

2) The magnetic field of a solenoid … a) Is strongest outside of the solenoid b) Is highly directional, along the axis of the solenoidc) Will be in the same direction regardless of the

direction of the current flowing through its wired) None of the above

Reading Quiz #16

1) Ferromagnetic materials can be made into strong permanent magnets

a) True b) False c) Depends on the exact composition

2) Which type of material will weaken the original (external) magnetic field?

a. Ferromagneticb. Paramagneticc. Diamagneticd. None of the above