1. Complete Quiz You have 10 minutes to complete the quiz The Quiz is Open-Book (use it) Get help from your neighbor

2. Quiz Review

3. 1) Open Circuit d) A circuit with the switch turned to off or a circuit with any break A circuit (a circle) must be complete for the switch to be “on” if there is any break or open spot, it is an “open circuit”.

4. 2) Closed Circuit f) A circuit with the switched turned on, or a completed circuit. A circuit (a circle) must be complete for the switch to be “on” if there are no breaks, it is a closed circle, or “closed circuit”

5. 3) Battery a) A device using chemical energy to push current in a circuit. A battery acts as a pump to push electrons through a circuit. In the last unit, we learned that a battery is a source of potential (stored) electrical enerergy.

6. 4) Resistance e) The ability to resist current flow. This is a property of materials that resists current flow, much like a kink in a hose or a bottle neck resists the flow of water. A resistor reduces the pressure (voltage) of the water flowing through it.

7. 5) Resistor h) In a circuit diagram, an object that uses electrical energy is usually represented by one of these. Any object, a bulb, a toaster, a piece of electronics can be a resistor.

8. 6) Ohm’s Law c) The mathematical relationship between current, voltage and resistance. Ohm’s law is represented by the equation: V = I x R, or I=V/R, or R = V/I

9. 7) Conductor g) An object through which electricity passes easily Any passage of electricity is said to be conduction. If it is easy, then the object or material is a conductor.

10. 8) Insulator b) An object that conducts electricity poorly Any passage of electricity is said to be conduction. If it does NOT conduct electricity easily, then it is an INSULATOR.

11. Question 9 A microwave uses a current of 4 amps to heat Mr. Franz’s coffee, The voltage in the wall outlet is 120 volts. Calculate the resistance of the microwave. Look at what we want, R R= V/I R=120 V / 4 A R=30  (ohms)

12. Question 10 A light bulb needs 2 amps to produce light. If the resistance of the bulb is 3 ohms, how many 1.5 volt batteries do you need to make it light? Look at what we want, V V=I x R V = 2A x 3  V = 6 V If each battery is 1.5 V, then we need 4 of them

13. Question 11/12 The diagram below pictures three identical light bulbs, each with a resistance of 1 ohm, which are connected by resistance-free wires. A 9-volt battery supplies energy to the circuit. The total resistance for the circuit shown in the figure is: Look at what we want, R For a series circuit, we just add the resistance R T = R 1 +R 2 +R 3 = 1  +1  +1  = 3 

14. Question 13/14 The current for the circuit shown is: The voltage drop across each light bulb above is ____ volt(s).

15. Question 15 Suppose you connect more and more light bulbs in series to a battery. What happens to the brightness of each bulb as you add more bulbs?

16. Question 16 The current in a series circuit:

17. Question 17 The current in a series circuit ( is always the same / may be different ) in different parts of the circuit.

18. Question 18 The voltage in a series circuit ( is always the same / may be different ) in different parts of the circuit.

19. Question 19 The current in a parallel circuit ( is always the same / may be different ) in different branches of the circuit.

20. Question 20 The voltage in a parallel circuit ( is always the same / may be different ) in different branches of the circuit.

21. Question 21 If each resistor is 2-ohms, what is the voltage drop across each resistor in the diagram below: What are we looking for?

22. Question 22 The voltage drop across each resistor in the circuit below is ____ volt(s). What are we looking for?

23. Question 23 The current in each resistor in the circuit is ____ ampere(s). The total current is ____ amps. What are we looking for? I = V/R This is a parallel circuit, so V is the same everywhere.

24. Question 24 What is the voltage drop across each resistor? What are we looking for? V This is a parallel circuit, so V is the same everywhere.