Regents Physics Circuits

Four identical light bulbs K, L, M, and N are connected in the electrical circuit shown above.

Rank the current through the bulbs.

• L = M > K = N

• L > M > K > N

• N > K > L = M

• N > L = M > K

Four identical light bulbs K, L, M, and N are connected in the electrical circuit shown above.

In order of decreasing brightness (starting with the brightest), the bulbs are:

• L = M > K = N

• L > M > K > N

• N > K > L = M

• N > L = M > K

Four identical light bulbs K, L, M, and N are connected in the electrical circuit shown above.

Bulb K burns out. Which of the following statements is true?

• All light bulbs go out

• Bulb N becomes brighter

• The brightness of bulb N does not change

• Bulb N becomes dimmer but does not go out

Four identical light bulbs K, L, M, and N are connected in the electrical circuit shown above.

Bulb M burns out. Which of the following statements is true?

• All light bulbs go out

• Bulb N goes out but at least one other bulb remains lit.

• The brightness of bulb N does not change

• Bulb N becomes dimmer but does not go out

Each member of a family of six owns a computer rated at 500 watts in a 120 V circuit. If all computers are plugged into a single circuit protected by a 20 ampere fuse, what is the maximum number of the computers can be operating at the same time? (Hint: figure out the current drawn by one computer first)

• 2

• 3

• 4

• 5

In the circuit shown in the image, the equivalent resistance of the three resistors is

• 15 Ohms

• 20 Ohms

• 50 Ohms

• 115 Ohms

A variable resistor (the resistance may be increased or decreased) is connected across a constant power supply. Which of the following graphs represents the power P dissipated by the resistor as a function of its resistance R?

• 
• 
• 
• 

Lightbulbs are typically rated by their power dissipation when operated at a given potential difference. Which of the following lightbulbs has the largest current through it when operated at the potential difference for which it's rated?

• 0.8 W, 1.5 V

• 6 W, 3 V

• 4 W, 4.5 V

• 8 W, 6 V

The batteries in each of the circuits shown above are identical and the wires have negligible resistance.

In which circuit is the current out of the battery the greatest?

• A

• B

• C

• D

The batteries in each of the circuits shown above are identical and the wires have negligible resistance.

In which circuit is the equivalent resistance connected to the battery the greatest?

• A

• B

• C

• D