battery to the external load, we can determine the power of the circuit, which is:
(3)
If we are to combine the first and third equation, then we will obtain a more usable
equation:
(4)
With just a quick look at this new equation, we can notice that either a large R
resistance or a small one will make the power approach zero.
Now, to obtain the
maximum value for power, the resistance needs to be at some moderate value.
This
means that the maximum power is obtained when R=r.
This is known as the load being
“matched” to the seat of the EMF. Now there are two types of resistance that the
components of an electrical circuit can be connected: parallel and series. Parallel just
means, “components…are connected so the same
voltage
is applied to each
component.”
[12]
Series just means, “Components…are connected along a single path, so
the same
current
flows through all of the components.”
[2]
To figure out the capacitance of
a capacitor in series use the equation:
In order to calculate the capacitance of a capacitor in series use the equation:
In order to make a higher internal resistance of a battery, the resistance should be
connected in series.
Equipment:
1.
DialBox resistor (110,000 ohms)
2.
100 milliampere meter
3.
5v voltmeter
4.
6 leads
1
http://en.wikipedia.org/wiki/Electromotive_force
2
http://en.wikipedia.org/wiki/Series_and_parallel_circuits
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3v battery with an internal resistor
6.
Contact switch
7.
Resistor
Procedure:
One must start off by setting up the circuit so that it matches the diagram above in
the theory section.
Then one has to set the external resistance to 300 ohms, close the
switch, and measure the readings on both the ammeter and voltmeter.
Then reduce the
resistance as it says in the table and record the current and voltage at each new resistance.
Then use this data to determine graphically the relationship between voltage and current
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 Spring '12
 Dr.Phaneuf
 Physics, Resistance, Volt, Faraday, PMAX, Ashley Cohen

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