Electromagnetic Induction
Practice Test
1.
You want to generate an
EMF
of 2.6 V by moving a wire at 3.0 m/s through a 0.040-T magnetic field. If you keep the wire perpendicular to the magnetic field, what length of wire should you use?
a.
22 m
b.
11 m
c.
0.046 m
d.
0.035 m
Hint
2.
A transformer goes from 10 V to 5000 V. How do the number of loops relate in the different coils?
a.
There are 5000 times more loops in the primary coil.
b.
There are 50 times more loops in the secondary coil.
c.
There are 500 times more loops in the secondary coil.
d.
There are 500 times more loops in the primary coil.
Hint
3.
In Figure 25-2, if the wire were moved to the left instead of the right, what would the direction of the magnetic force on it be?
a.
down
b.
into the page
c.
up
d.
out of the page
Hint
4.
A step-down transformer has 80,000 turns on its primary coil and 500 turns on its secondary coil. If the primary coil is attached to a generator with an
EMF
of 45.0 V, what is the
EMF
in the secondary coil?
a.
7.20×10
3
V
b.
3.56 V
c.
0.281 V
d.
1.39×10
-4
V
Hint
