Unit 4 Post Test: Circuitry

Which item(s) would be sufficient to make a circuit?

• conductor

• insulator

• conductor and battery

How much power is produced by a flashlight that has a voltage of 12 volts and a current of 6.5 × 10^-2 amps?

• 0.78 watts

• 78 watts

• 190 watts

To which is the watt equal?

• joules/second

• joules/coulomb

• volts/second

Fuel cells have been developed that can generate a large amount of energy.

For example, a hydrogen fuel cell works by combining hydrogen and oxygen gas to produce water and electrical energy. If a fuel cell can generate 10.0 kilowatts of power and the current is 15.8 amps, what is the voltage of the electricity?

• 158volts

• 633 volts

• 158,000 volts

Tags

NGSS.HS-PS3-1

NGSS.HS-PS3-5

What is the equivalent resistance in a parallel circuit that has the following three resistors: 6.8 ohms, 9.0 ohms, and 15.0 ohms?

• 10.3 ohms

• 3.08 ohms

• 80 ohms

In a series circuit, what effect will adding more resistors to the circuit have?

• It will decrease the equivalent resistance which will decrease the total current.

• It will increase the equivalent resistance which will decrease the total current.

• It will increase the equivalent resistance which will increase the total current.

A combined circuit has two resistors in parallel (34.0 ohms and 41.0 ohms) and another in series (15.0 ohms). If the power source is 9.0 volts, what will the current be?

• 0.054 amps

• 3.36 amps

• 0.27 amps

Which statement is true for a series circuit?

• As more resistors are added, the current will increase.

• The average of the voltage drops will be the total voltage in the circuit.

• The current is the same across all resistors in the circuit.

A large electrical device is plugged into a 240-volt outlet and has a resistance of 160 ohms. How much power does the device use?

• 1.5 watts

• 360 watts

• 100 watts

Tags

NGSS.HS-PS3-3

If the resistance remains constant and the voltage doubles, what effect will that have on the power?

• The power will remain the same.

• The power will increase by a factor of 2.

• The power will increase by a factor of 4.