1.
Which one of these has an electromotive force that makes a rod slide?
a.
solenoid.
b.
relay.
c.
both.
2.
Which of these depend upon EMF as the power to operate?
a.
alternator.
b.
generator.
c.
both of these.
3.
In a step-down transformer, the voltage goes which way?
a.
from high to low.
b.
from low to high.
c.
stays the same but the current drops.
4.
What causes electromotive forces?
a.
high voltage in a cirular wire.
b.
hot resistance emissions.
c.
magnetic field through a core.
5.
The ''coil'' in your car is actually one of these?
a.
a capacitor.
b.
a big resistor.
c.
a transformer.
6.
The output voltage from your cars' ''coil'' is much higher than the input curcuit side. Why?
a.
the high power is need to start the battery.
b.
the high output is needed to send high power to the sparkplugs.
c.
the low power input curcuit is kept safe from dangerous magnetic fields.
7.
If the power in both coil of a transformer is equal and there is 40volts and 2 amps primary coil on the left and a 5 ma secondary coil, what is the secondary voltage?
a.
40 milliamps .
b.
80 kv.
c.
16 kv.
8.
Magnetic lines of force changing in intensity in one coil inducing an emf in the other coil is called?
a.
mutual induction.
b.
mature reduction.
c.
coupling coefficient.
9.
A diode in the secondary of an a.c. transformer is often used to change the sinusoidal output to one of these.?
a.
a smooth average current.
b.
double the voltage.
c.
half-wave rectified.
10.
Which of these has a large transformer on the back of it, that people usually call a big magnet?
a.
an amplifier.
b.
a speaker .
c.
an alternator.