1. Ohms Law, current electricity, series circuits

3. Electric Current
The continuous flow of electrons through a conducting metal.

4. Alternating Current
Flow of current that periodically changes direction
Produced in power plants
Current from a wall outlet changes direction 120 times per second

5. Direct Current The flow of current in one consistent direction
Examples
Batteries
Solar cells
Current from a battery travels from the positive terminal to the negative terminal.

6. Common Language

7. Note Taking Guide Quantity Symbol Definition Unit Measuring Device
voltage
current
resistance

8. Voltage
Voltage (V) (also know as Potential Difference) can be thought of as the force pushing electric charges along a conductor. It is the energy in the circuit
Measured in Volts (V)

9. electric potential difference, must be connected in parallel
Voltmeter
a device that measures
electric potential difference,
must be connected in parallel

10. Current
Electric current (I) is the movement of electric charge in a conductor (rate at which the electrons are flowing)
Measured in Amps (A)

11. a device that measures current
Ammeter
a device that measures current
attached in series

12. Resistance
Resistance (R) is a measure of how difficult it is to push the charges along.
The energy is transformed at the resistor (potential energy is converted).
Examples: light bulb, charging your phone, making coffee, etc.
Measured in Ohms ()
An Ohmmeter is used to measure resistance in a system.

13. Note Taking Guide Quantity Symbol Definition Unit Measuring Device
voltage V
Energy in the circuit
Volts
Voltmeter
current I
Rate of flow
Amps
Ammeter
resistance R
Opposes current; energy transforms
OhmsΩ
Ohmmeter

14. Ohm’s Law
Ohm's Law analyzes the relationship between voltage and current in an ideal conductor.
Ohm's Law is given by:
V = I * R

15. Example
A flashlight that is powered by 3 volts and uses a bulb with a resistance of 60 ohms. What is the current flowing through the circuit?

16. Example
A flashlight that is powered by 3 volts and uses a bulb with a resistance of 60 ohms. What is the current flowing through the circuit? G: V = 3 volts E: V = (I)(R) S: 0.05 Amps R = 60 Ω S: 3 = (I)(60) U: I

17. Practice

19. Series Circuits
Resistors can be connected in series; that is, the current flows through them one after another.

20. Kirchhoff’s Rules
Loop Rule: The sum of the potential differences (voltage) around any closed circuit loop is zero.

21. Kirchhoff’s Rules
Loop Rule: The sum of the potential differences (voltage) around any closed circuit loop is zero.

22. Series Circuit RT = R1 + R2 + R3 + ... IT = I1 = I2 = I3 = ...
1. total resistance is the sum of the
separate resistors
RT = R1 + R2 + R
2. current is the same through each resistor
IT = I1 = I2 = I3 = ...
3. total potential difference is the sum of each
VT = V1 + V2 + V
In other words, in a series circuit,
resistance and voltage add,
but current stays the same.

23. Series Circuit Example

24. Series Circuit Practice