What do you think the role is of the resistor in this circuit?
1. It is to limit the flow of electricity through the circuit.
What does your observation tell you about diodes (and LEDs)?
2. The LED’s only lighting up in one direction shows that the conductivity will only
work in one direction.
3. 4.96
What is happening on the display each time you make the range smaller?
4. 4.8
5. The lower it voltage it went the lower it read.
6. The energy would rather go through the ohmeter than the circuit, so therefore
there is no voltage through the circuit.
7. 1.54 V. The reading showed around 1.7 which was obtained by dividng 5/330.
8. Using Ohm’s Law (V=IR). The current flowing through the 330Ω resistor would be
approximately 9.09 milliamps (mA) or 0.00909 A.
9.
(a) If you were to touch the DMM across both R1 and R2, you would expect the
voltage to read 4.5V. This is because the two identical 330Ω resistors are in series
with each other, so the voltage is divided equally between them.
(b) Due to R1 and R2 being identical, I would say that the voltage across each resistor
is individually 4.5V due to it being in series.
(c) The value of the equivalent resistor would be 660Ω (330Ω + 330Ω).
Create this series circuit on your breadboard with a 5V power source. With both LEDs
illuminated, remove one of the LEDs from the circuit path. What happened and why?
10. Due to it being in series the lack of the second LED will provide more energy to the
breadboard allowing the light to shine brighter.
You can try 3 LEDs in series but none will light up. Why do you think that is?
11. They could not light up due to the current not having enough to supply the third led
to light up.
Components in a circuit can also be arranged in parallel. Create this parallel circuit on
your breadboard. With both LEDs illuminated, what happens if you remove one of the
LEDS from the circuit path?
12. When you remove one of the LEDs the lights stay on when you add the
third the first LED gets turned off and the third lights up.
Using the diagram for a series circuit shown to you in Step 9 as a reference, can you
draw a circuit diagram showing 2 resistors in parallel? (Draw circuit below.)
13.
In a series circuit, all components have the same current (Amps) flowing through them
(even if the resistors have different values). That is not the case for components in
parallel with each other. What do components in parallel have in common?
14. Same voltage but different current
Based on your observations and what you have learned about parallel circuits, use
Ohm’s Law (V=IR) to calculate the current in each of the 3 resistors.
15.
R1. 1.1 Amps
R2. 0.45 Amps
R3. 1.8 Amps
16. The total current will increase for each added resistor. This is because more
current being drawn out of the battery, due to added resitance from the resitors
as well as the cables.
Conclusion
1. Describe the proper way to place the DMM leads and the steps you use to attain the
most precise measurement value for voltage across components using a Digital
Multimeter (DMM). The proper way to attach the ohmmeter leads to the circuit is to
strip the wire to where there is a bit of conducting piece exposed. Then to
connect the ohmeter to the piece of exposed wire and then another component
throughout the circuit. This will measure the voltage or the current across the
circuit, telling different pieces of information about the resistance of the overall
circuit.
2. If the value on the DMM is negative, what does that tell you about the orientation of
the DMM leads in relation to the flow of conventional current? This means that the
elections flow in the opposite direction
3. LEDs and resistors transfer electrical energy into light and thermal energy. What is an
important characteristic about LEDs (and diodes) that make it unique compared to a
resistor?
LEDs have many characteristics that sets them apart from resistors. Leds only
allow the current to flow in one direction. LEDs also are able to emit light when
the current is passed through them, making them useful for many applications.
4. In your own words, describe what it means for components to be in series with each
other. What characteristic do components in a series always have in common?
(Voltage, Current, or Resistance)
When the components are in series they share a few characteristics that
distinguishes them from others. In series components are connected end to end
for one path flow. This is similar to christmas lights, when one component is
removed or burns out the rest in the path will turn off.
5. In your own words, describe what it means for components to be in parallel with each
other. What characteristic do components in parallel always share in common?
(Voltage, Current, or Resistance)
When components are in parallel with each other it means that they are
connected side by side. So this allows current to flow through each one
independently. The components in parallel share the same voltage across them.
The current that flows through each component can change depending on its
individual resistance. So, voltage is the characteristic that both series and
parallel always share in common.