Transcript Electromagnets

Review Game Eureeka
Obtain a board, marker, wipey-thing
and partner
1. Draw a series circuit containing
at least two resistors and a battery
2. Add an ammeter and a
voltmeter to correctly measure
quantities in your circuit
3. Compare to the potential drop
across an ammeter, the potential
drop across a voltmeter is
1.
2.
3.
Greater
Less
The same
4. Compared to the current through
an ammeter, the current through a
voltmeter is
1.
2.
3.
Less
Greater
The same
5. Compared to the internal
resistance of an ammeter, the
internal resistance of a voltmeter is
1.
2.
3.
Less
Greater
The same
Complete the following sentence:

6. An ammeter is a galvanometer with . . .
A low resistance in parrallel

7. A Voltmeter is a galvanometer with . . .
A high resistance in series
8. The function of the iron core in
the galvanometer is to . . .

Magnify the strength of the magnetic field
9. As the current passing through
the coil of a galvanometer decreased,
the degree of deflection on the coil
1.
2.
3.
Decreases
Increases
Remains
the same
10. A device that converts electrical
energy into rotational mechanical
energy is a
1.
2.
3.
4.
Generator
Laser
Motor
Transformer
11. What does the split-ring
commutator in a motor do?
It allows for complete rotation of the
armature core.
12. As the armature of an operating
electric motor rotates, a back EMF is
induced in the armature. Compared
to the applied EMF, the net EMF in
the armature is
1.
2.
3.
Less
Greater
The same
Refer to the picture on the board for
the following (note to self, it’s a loop
in a B-field)



13. The magnetic force on the loop at P is in
which direction?
14. If the current in the loop increases what
will happen to the magnetic force on the loop
15. If a stronger magnet is used, how will the
magnetic force be effected?
16. A device used to measure a
WEAK current is called a . . . ?

GALVANOMETER
17. As an electron is shot between a
pair of oppositely charged parallel
plates. Which plate does it arc
towards?
1.
2.
3.
Positive
Negative
Neither
18. An electron located between two
oppositely charged parallel plates is
accelerating toward the + plate. As
the Voltage between the plated
decreases, the acceleration of the
electron
1.
2.
3.
Decreases
Increases
Remains the same
19. A device used to separate
isotopes of the same element is called
a
1.
2.
3.
4.
Laser
Mass spectrometer
Split-ring commutator
Transformer
20. Who determined the charge of
an electron?
Milikin
In his oil-drop experiment
N

A
S
21. During one complete rotation of the
loop, the direction of the current in the loop
on side A can be symbolized by
1.
2.
3.
4.
Xxxxxxx
Ooooooo
Both xxx and oooo
Neither xxx or ooooo
N

S
21. Looking at the momentary placement of
the loop, the induced potential difference in
the left side of the loop will be
1.
2.
3.
4.
Xxxxxxx
Ooooooo
Both xxx and oooo
Neither xxx or ooooo
The primary coil of a transformer
with an efficiency of 100% has 200.
turns and its secondary coil has 50.
turns. The primary coil is connected
to a 120-V AC Power supply and
develops 600-W of Power.
22. What is the Potential difference
across the secondary coil?
23. What is the current in the
primary coil?
24. What is the power developed in
the secondary coil?
We will do quick review tomorrow
and then you will take your exam