Ohm's Law, Power & Circuits Review

The current in a circuit is...

• A. directly proportional to the resistance and inversely proportional to the voltage.

• B. directly proportional to the voltage and inversely proportional to the resistance.

• C. directly proportional to both the voltage and resistance.

• D. inversely proportional to both the voltage and resistance.

The following circuits consist of a single resistor and a battery. Which circuit will have the greatest current?

• 9-V battery & 10-Ω resistor

• 9-V battery & 20-Ω resistor

• 18-V battery & 10-Ω resistor

• They will all have equal currents.

Resistance in a wire depends on its...

• length

• thickness

• resistivity

• all of these

Which of the following would have the most resistance?

• long, thin wire

• long, thick wire

• short, thin wire

• short, thick wire

When connected to a 220-volt supply, how much current exists in a light bulb that has a resistance of 240 Ω?

• .91 A

• 1.9 A

• 2 A

• 0.5 A

If the voltage across a circuit is decreased and the resistance increased, the current will ____.

• decrease

• increase

• not change

Which of the following statements is FALSE for a series circuit consisting of a battery and three bulbs?

• A. The total resistance is equal to the sum of the bulbs' resistances.

• B. If one of the bulbs burns out, all the bulbs will go out.

• C. The brightness of the three bulbs will decrease if a fourth bulb is added.

• D. The current is the same throughout the circuit.

• E. If one of the bulbs burns out, the others will still work.

Which type of circuit is it?

• series

• parallel

What is the total resistance of the circuit?

• 1.5 Ω

• 2 Ω

• 18 Ω

• 150 Ω

What is the current through the battery?

• 0.5 A

• 2 A

• 5.7 A

• 27 A