Download Name__________________________ GS104 Homework

Name__________________________
GS104 Homework #14
Dr. John Carlson
Show your work.
1. The SI unit of magnetic field is the Tesla, abbreviated T.
2. Another smaller unit of magnetic field is the Gauss.
3. The magnetic field lines around a straight current-carrying wire are straight lines pointing
perpendicularly away from the wire. ( T / F )
4. Sketch a few lines of magnetic field B for this straight current-carrying wire.
(Be sure to put arrow heads on all field lines to indicate direction)
I
5. A solenoid is a coil consisting of many loops of wire.
6. Sketch a line of magnetic field B at the center of this loop of current-carrying wire.
B
I
7. Unlike an electric field line, which begins at a positive charge and terminates at a
negative charge, a magnetic field line is always a closed curve, which in the case of a bar
magnet goes out of the north pole and into the south pole. ( T / F )
8. The Earth has a magnetic field which arises from electric currents in its liquid core.(T /F)
9. Unlike magnetic poles attract. ( T / F )
10. Sketch a line of magnetic field B around this bar magnet.
N
S
11. (Fill in the blanks) In order for there to be a magnetic force ona particle, the particle
must have charge, and it must be moving with a non-zero velocity relative to an
externally supplied magnetic field. If however, the velocity vector, v, is parallel to the
magnetic field vector, B, the force is zero.
12. For each situation of a charged particle moving in the presence of a magnetic field, state
whether the direction of the force on the particle is into or out of the place of the paper, or
zero. In each case, a + or – indicated whether the charge is positive or negative.
B
a.
B
b.
B
c.
v
v
+
v +
d.
e.
v –
B
B
a. into
d. zero
f.
B
v +
v
b. zero
e. out of
c. into
f. out of
–
–