Name_____________________________________
Circuit Analysis and Ohm’s Law
https://phet.colorado.edu/sims/html/circuit-construction-kit-dc/latest/circuit-construction-kit-dc_en.html
1. Construct the following circuit. Are the components arranged in series or in parallel?
Voltage Rules
Measuring voltage with a voltmeter https://www.youtube.com/watch?v=_jjIDdWwgms
(If you have a multimeter at home, you can the voltage on all of your batteries by simply touching the leads to
each end of the battery try it in the sim)
2. Use the virtual Voltmeter to measure the voltages
across.
a. The Battery _______________
(move the black probe into the contact circle)
b. The Switch ________________
c. The Lamp (lightbulb) +________________
(shown to the right))
d. The pencil +________________
Total of b+c+d
= ________________
a
c
How does the voltage supplied by the battery compare to the voltage used by the other components added
together? Use what you know about voltage to explain why that happens.
Current Rules
Measuring current with an Ammeter (current meter) https://www.youtube.com/watch?v=P660hTqkGiY
3. Remove the component listed and use the Ammeter to re-connect the points to measure the current through
the segment of the circuit.
a
b.
c. How do you think you would
find the current on the right
side of the lamp?
What is the current coming out
of the battery-when the
ammeter replaces the switch?
What is the current coming out
of the pencil-when the
ammeter replaces the wire
between the pencil and the
lightbulb?
What is the current coming out
of the lamp?
What do you notice about the current coming out of the battery, compared to the current coming out of the
pencil, compared to the current coming out of the bulb? Use what you know about how current moves in a
circuit to explain why that happens.
What happens to the components in the circuit if one component is removed if the opening is not bridged by
the ammeter? Use what you know about current and circuits to explain why this happens.
4. Lamp Analysis
a Use the current going into the lamp and the voltage
b. Use the current going into the lamp and the
drop across the lamp to calculate the power
voltage drop across the lamp to calculate the
(brightness) of the bulb? Calculate using P= IV,
resistance of the lamp. Calculate using V=IR
5. Pencil Analysis
a Use the current going into the pencil and the
voltage drop across the pencil to calculate the power
(heat) dissipated by the pencil? Calculate using P= IV,
b. Use the current going into the pencil and the
voltage drop across the pencil to calculate the
resistance of the pencil. Calculate using V=IR
6. ____What circuit parameter do all series components have in common?
a. resistance
b. current
c. voltage
d. power
Another type of circuit
7. Construct the following circuit. Are the components arranged in series or in parallel?
8. Use the Voltmeter to measure the voltages across.
a. The Battery _______________
b. The Pencil _________________
c. The lamp ________________
How does the voltage across the battery, compare to the voltage across the
pencil, compare to the voltage across the lamp? Why do you think this
happens?
9. Remove the component listed and use the Ammeter to re-connect the points to measure the current through
the segment of the circuit
a. Remove the switch to find the current coming out of the battery _____________
b. Remove the wire to the left of the pencil to find the current going into the pencil _____________
c. Remove the wire to the left of the lamp to find the current going into the lamp ____________
What do you notice about the current coming out of the battery compared to the current going into pencil
and into the lamp? Use what you know about how current moves in circuits to explain why.
Complete the following equation by placing
a +, -, or = in the blanks. There is more than one
right answer
(The letter I is used for current)
Ibattery _____Ilamp______Ipencil
What happens to the components in the circuit if one component is removed if the opening is not replaced by
the ammeter? Use what you know about circuits to explain why.
10. Lamp Analysis
a Use the current going into the lamp and the voltage
drop across the lamp to calculate the power
(brightness) of the bulb? Calculate using P= IV,
b. Use the current going into the lamp and the
voltage drop across the lamp to calculate the
resistance of the lamp. Calculate using V=IR
11. LED Analysis
a Use the current going into the LED and the voltage
drop across the LED to calculate the power
(brightness) of the LED? Calculate using P= IV,
b. Use the current going into the LED and the voltage
drop across the LED to calculate the resistance of the
LED. Calculate using V=IR
12. ____What circuit parameter do all parallel components have in common?
a. resistance b. current
c. voltage
d. power