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Chapter 24 Magnetism
1) Several paper clips dangle from the north pole of a magnet. The
induced pole in the bottom of the lowermost paper clip is a
A) north pole.
(north always on top if south is on bottom)
B) south pole.
C) north or south pole - no difference really.
2)
A)
B)
C)
D)
Surrounding every moving electron is
an electric field.
a magnetic field.
both of these.
(moving charge creates a ΔE  B, see #12)
none of these.
3)
A)
B)
C)
D)
Magnetic field lines about a current-carrying wire
extend radially from the wire.
circle the wire in closed loops.
both of these.
neither of these.
4) The magnetic north pole of the earth is nearest
A) Australia.
B) the Hudson Bay region of Canada.
C) both of these.
5) Magnet A has twice the magnetic field strength of Magnet B
and at a certain distance pulls on magnet B with a force on B of 100
N. The amount of force that magnet B exerts on magnet A is (that is
the force on A is)
A) exactly 100 N.
Newton’s 3rd law (action-reaction)
B) at or about 50 N.
C) more information is needed.
6) A magnetic field points straight up in the plane of this page. An
electron is shot from the right, and is moving toward the left. The
electron
A) is deflected into the plane of the page.
(right hand rule)
B) is deflected out of the plane of the page.
C) is deflected up along the magnetic field in the plane of the page.
D) is deflected down opposite the magnetic field in the plane of the
page.
E) none of these.
7) If a compass is moved from the northern hemisphere to the
southern hemisphere, its magnetic needle will change direction
A) depending on where the measurement is taken.
B) by 180 degrees.
C) by 90 degrees.
D) hardly at all. (since not exactly at the north pole, thus barely moves)
E) none of these
8)
A)
B)
C)
D)
Which force field can increase a moving electron's speed?
Electric field.
Magnetic field. (B  can only change direction, not speed)
Both of these.
None of these.
Chapter 25 Electric Induction
9) The magnetic field strength inside a current-carrying coil will be
greater if the coil encloses a
A) glass rod.
B) wooden rod.
C) vacuum.
D) rod of iron.
(increase permeability of free space with ferromagnetic core)
E) none of these.
10) The output power of a transformer is
A) equal to the input power.
B) greater than the input power.
C) smaller than the input power.
D) ...may be any of these.
11) Power is transmitted at high voltages because the
corresponding current in the wires is
A) also high to deliver appreciable power to distant places.
B) low so that overheating of the wires is minimized. (low compared to V)
C) both of these.
D) neither of these.
12) Rapid change of a magnetic field induces
A) an electric field.
B) a magnetic field of greater magnitude.
C) a magnetic field of the same magnitude.
13) Metal detectors, like the ones used at airports, are activated
by
A) alternating current.
B) electric fields.
C) magnetic fields.
D) electromagnetic induction.
(Metal core increases B)
14) The voltage across the input terminals of a transformer is 110
V. The primary has 50 loops and the secondary has 25 loops. The
voltage the transformer puts out is
A) 25 V.
B) 55 V.
Vin/Vout = Nin/Nout (N is number of coils)
C) 110 V.
D) 220 V.
E) none of these.
15) Disregarding the effects of friction, a cyclist will coast
farther when a lamp powered by a wheel generator is
A) of low wattage.
B) burned out.
C) of high wattage.
D) none of these.