Circuit questions

1.  Describe the difference between voltage, current, and resistance.  Give the proper units, too.

2.  What is the resistance of a light bulb that allows 2 A of current through it when connected to a 12-V battery?  (6 ohms)

3.  A 5-ohm resistor is connected to a 10-volt battery. What current goes through the resistor?  (2 amps)

4.  In general, what is the difference between resistors in series and in parallel?  Recall the light bulb examples and how the brightnesses compare.

5.  Which has more resistance, 2 identical bulbs in series or the same 2 identical bulbs in parallel?

6.  For question 5, which set-up (series or parallel) would "kill" the battery quicker?

7.  You have 2 bulbs in series - remove one (unscrew it) and what happens?

8.  You have 2 bulbs in parallel - remove one (unscrew) and what happens?

9.  Draw the symbols for battery, resistance and wire.  Draw a schematic for 2 resistors in series.  Draw a schematic for 2 resistors in parallel.

10.  Recall the basics of what it takes to make a light bulb light.  Also recall the various light bulb brightness demonstrations from the past 2 classes.

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