Transcript Don`t forget to put your names on your report

The Physics of
Electricity and
Magnetism
Activity: Being a
Part of a Current
Event
9-12 Science Std: Phys 5h, 5j
In this activity we will be:
1. Seeing how a moving magnetic field
induces (makes) an electric potential
2. Measuring how much voltage
and current can be made
3. Comparing our generator with a
known power source
So here we go
Pick up the equipment you will need to do the
activity from the side counter
1 multimeter
2 wire
connectors
Cell phone
battery info
1 ammeter
1 D-Cell
battery
1 bar magnet 1 test tube
generator
A calculator Paper and
pen/pencil
Verify you have all of the items listed here
How to use the Multimeter
1. Look at the dial of the
multimeter
You will see 2 symbols
that you will be using:
V
And
A
These stand for:
And Current
Voltage (V for volts)
(A for Amps)
How to use the Multimeter
2. Turn the dial to the 20
position under on the voltage
side
Take the red test lead
on the multimeter and
touch it to the positive
(+) terminal on the
battery
Take the black test
lead on the multimeter
and touch it to the
negative (-) terminal
on the battery
You should read about
1.5 volts
Start Your set up:
1. Clear off the table and put
the “test tube generator” in the
center of the table
2. Connect the red wire leads
to copper wire on the generator
– one wire on each end
Start taking readings
3. Take your ammeter and
loosen black and red terminal
screws on the front
4. Attach the red wires on the
test tube generator to the 2
terminals on the ammeter
5. Take the bar magnet and
slowly put it inside the test tube
See if there is any movement on the
ammeter – if not raise your hand
Start taking readings
6. Move the magnet in and out
of the test tube to try to get the
biggest current reading you can
7. When you get the biggest
current reading you can, write
down the maximum current
We will use this number later
Start taking readings
8. Disconnect the test tube
generator from the ammeter
and connect it to the two test
leads on the multimeter
9. Turn the dial on the
multimeter to “m 200” under the
voltage side
The numbers you will see are
in milivolts (or 1/1000 of 1
volt)
Start taking readings
10. Move the magnet in and
out of the test tube to try to get
the biggest voltage reading you
can
11. When you get the biggest
voltage reading you can, write
down the maximum current
We will use this number later
Analyze your readings
Question and Answer Report
Don’t forget to put
your names on
your report
1. Compare the current you made with the generator:
Take the number of amps your cell phone battery
can put out and divide it by the maximum amp
reading you got from your generator then multiply
that number by 1000 to adjust for the units
Example: (950 mAh / 100 μA)(1000)
This is the number of test tube generators that you
would need to use to make the same amount of
current that your battery can produce
Record your calculations and answer on your report
Analyze your readings
Question and Answer Report
Don’t forget to put
your names on
your report
2. Compare the voltage you made with the generator:
Take the voltage your cell phone battery can put out
and divide it by the maximum voltage reading you
got from your generator then multiply by 1000 to
adjust the units
Example: (3.7 V / 30 mV)(1000)
This is the number of test tube generators that you
would need to use to make the same amount of
voltage that your battery can produce
Record your calculations and answer on your report
Analyze your readings
Question and Answer Report
Don’t forget to put
your names on
your report
3. Answer the following questions:
a. While you moved the magnet in and out of the
test tube, did the values change or were they
constant?
b. What factors affect how big your readings are?
In this experiment, what factors could you change?
c. If you could change something in this experiment
to make a generator that could power your cell
phone, what would you change?
End of Activity
Clean-Up
In the last 5 minutes of class:
Put all of your materials back on the side
counter
Clean up your table work area
Turn in your report for this activity
Don’t forget to put your team
member’s names and the period # at
the top of the sheet.