chapter 9 RAT Flashcards
The source of all magnetism is
A. tiny bits of iron.
B. tiny domains of aligned atoms.
C. small loadstones.
D. the motion of electrons.
D. the motions of electrons
Surrounding moving electric charges are
A. electric fields.
B. magnetic fields.
C. both of these
D. neither of these
C. both of these
A magnetic force acts most strongly on a current- carrying wire when it is
A. parallel to the magnetic field.
B. perpendicular to the magnetic field.
C. either or both of these
D. neither of these
B. perpendicular to the magnetic field
A magnetic force acting on a beam of electrons can change
A. only the direction of the beam.
B. only the energy of the electrons.
C. both of these
D. neither of these
A. only the direction of the beam
When you move a bar magnet to and fro, first thrusting it into, and then withdrawing it from, a coil of wire, you induce
A. direct current.
B. alternating current.
C. neither dc nor ac.
D. alternating voltage only, not current.
B. alternating current
The principle underlying the operation of an electric motor is that
A. electric and magnetic fields repel each other.
B. a current-carrying wire experiences force in a magnetic field.
C. like magnetic poles both attract and repel each other.
D. ac voltage is induced by a changing magnetic field.
B. a current-carrying wire experiences force in a magnetic field
The essential physics concept in the operation of an electric generator is
A. Coulomb’s law.
B. Ohm’s law.
C. Faraday’s law.
D. Newton’s second law.
C. Faraday’s law
A transformer works in accordance with
A. Coulomb’s law.
B. Ohm’s law.
C. Faraday’s law.
D. Newton’s second law.
C. Faraday’s law
A step-up transformer in an electric circuit can step up
A. voltage.
B. energy.
C. both of these
D. neither of these
A. voltage
Electricity and magnetism connect to form
A. mass.
B. energy.
C. ultra-high-frequency sound.
D. light.
D. light
