Download 8thEnergyLabStation6

STATION #6: Electrical and Mechanical Energy
Electricity and magnetism are related to each other. A magnetic
field can produce an electrical current, and vice versa. Two
instruments, called a motor and a generator, take advantage of this
fact. A hand-powered flashlight contains a generator. Electric motors
are used in many applications, including fans, electronic toys and cell
phones. Here we will examine how generators and motors work.
Background
To see how electricity and magnetism are connected, make a circuit
as shown on the Electromagnet Circuit sheet. You have created an
electromagnet. Press and hold the switch and move the compass in a
circle near the electromagnet. Observe what happens. Release the
switch and move the compass again. What do you notice?
An electric current flowing in a wire has a tiny magnetic field. By
looping a long wire into a coil, the tiny magnetic field is concentrated
into a large one, able to attract magnetic objects.
Part I. If we depress the handle of the flashlight, then the flashlight
will _______________ because _______________.
Hypothesis
Procedure
Discussion
Conclusions
Part II. If we connect a motor to a battery, the motor will
_______________ because _________________.
Part I. Hand-powered flashlight: generator
a) Squeeze the handle to light up the flashlight.
b) Look what happens inside the flashlight when you squeeze the
handle. Note what type of energy you put in, and what
transformations it goes through within the flashlight.
Part II. Electric motor
a) Examine the electric motor that has been taken apart. Identify
the coil of wire on a shaft and the small magnets.
b) Connect the whole motor to a battery using the cables.
Observe what happens.
c) Switch the clips to the opposite terminals of the battery. Note if
anything is different.
How are motion and electricity connected? What applications make
use of this phenomenon?
Part I. A generator converts
____________________ energy to____________________ energy.
Part II. An electric motor converts
____________________ energy to____________________ energy.
In both cases, energy is lost in the forms of _____________________________.
Electromagnetism
Use the electromagnet circuit to explore electromagnetism.
• Can you decorate the Wooly Willy with the electromagnet?
Extensions/
• Loop two paper clips together. Hold them near the magnet and
Applications
move them around to see the magnetic field. Are there places where
the magnetic field is stronger or weaker?
• Draw a diagram of the electromagnet and draw the magnetic field
lines around it.