1. WARM UP 1. In this circuit: a. Where is the voltage? b. Where is the current? c. Where is the resistor? 2. Identify the following circuit symbols: a.a. b.b. c.c.

2. WARM UP 1. In this circuit: a. Where is the voltage? b. Where is the current? c. Where is the resistor? 2. Identify the following circuit symbols: a.a. b.b. c.c. Battery Wire Bulb Battery Switch Bulb

3. LET’S MAKE A CIRCUIT The human body is a conductor (although not as good as materials such as copper) When the contacts on the energy balls are connected by a conductor, they make a sound and light up.

4. PHET SIMULATION Phet.Colorado.edu Search for: Circuit construction kit [DC only]

5. Ohm’s Law: Describes the relationship between resistance, current, and voltage in electric currents. V=IR V equals the voltage in the circuit I equals the current flowing R equals the resistance of the electrical device in the circuit. or V/I = R

6. SERIES CIRCUIT: OHM’S LAW What happened to the voltage across the bulb when the resistance went up? It increased Describe the voltage through the whole circuit. It varies across each resistor (bulbs). Adding the voltages across each of the bulbs gives the total voltage-the voltage across the battery.

7. What happened to the current when the resistance went up? It decreased. Describe the current through the circuit. The same for the whole circuit. SERIES CIRCUIT: OHM’S LAW

8. What happened to the voltage across the bulb when the resistance went up? It stayed the same Describe the voltage through the whole circuit. It is the same through the whole circuit. PARALLEL CIRCUIT: OHM’S LAW

9. What happened to the current when the resistance went up? It decreased. Describe the current through the circuit. The sum of the currents of the individual branches equals the current through the whole circuit (through the battery). PARALLEL CIRCUIT: OHM’S LAW

10. OHM’S LAW V=IR Given a 6 volt (V) battery and a 2 ohm ( Ω ) resistor, how much current will flow? 6 = I · 2 I = 6/2 I = 3 Amps

11. TICKET OUT THE DOOR Draw a simple diagram of 1. A series circuit 2. A parallel circuit