Physics 121 General Physics
Concept Quizzes
Chapter 27 Current and Resistance
Chapter 28 Direct Current Circuits

Consider a car battery with a thick wire connected between its terminals as shown.

1. Which way does the electric field in the wire point?

	To the left.
	To the right.
	We cannot tell.

2. If positive charges cound move in the wire, which way would they move?

	To the left.
	To the right.
	We cannot tell.

If we double the length of the wire pictured, leaving everything else the same, what happens to the current in the circuit?

	It doubles.
	It halves.
	It is four times.
	It is the same.

Two resistors are wired in series. The second resistor has twice the resistance as the first. Current passes through the combination. Compared to the current through the first resistor, the current through the second resistor is

	the same.
	one half.
	smaller, but not necessarily half.
	one quater.

A and B are identical light bulbs.

1. When the switch is closed

	all the current tha flows through the battery continues to flow through bulb B.
	half of the current tha flows through the battery flows through the switch and half flows through bulb B.
	all the current tha flows through the battery flows through the switch.
	None of the above.

2. When the switch is closed the brightness of bulb A

	increases.
	remains unchanged.
	decreases.

If the four light bulbs in the circuits shown below are identical, which circuit puts out the most light?

	Circuit I.
	Circuit II.
	Both circuits emit the same amount of light.