Circuit basics

A resistor in a circuit has a potential difference of 20 V across it. The current through the resistor is 0.4 mA.What is the resistance of the resistor?

Which of the following is the correct unit for potential difference?

• Ohm

• Ampere

• Watt

• Volt

How many millivolts are there in 0.5 volts?

• 5

• 5000

• 50

• 500

Benjamin wants to find out the resistance of a resistor. He connects the resistor to a variable potential difference power source and uses an ammeter to find the current through the resistor. His results are shown in the table. What is the resistance of the resistor?

Ammeters should always be connected in________ .

Voltmeters should always be connected in ________.

• series, series

• parallel, parallel

• series, parallel

• parallel, series

The diagram shows an electric circuit consisting of a cell and a bulb. If the potential difference across the bulb is 1 volt and the current through the bulb is 1 ampere,what is the resistance of the bulb?

If a component in a circuit has lower electrical resistance, is it easier or harder for charges to move through it?

• Harder

• Easier

Which of the following is the correct definition of an electrical conductor?

• A material that is easy for charge to flow through

• A material that is hard for charge to flow through

Four identical resistors are placed in series in a circuit. The resistance of all four resistors together is 36 Ω.What is the resistance of each resistor individually?

• 9 Ω

• 12 Ω

• 6 Ω

• 3 Ω

A battery supplying 12 V is connected in series with two resistors. The potential difference across the first resistor is 4 V.What is the potential difference across the second resistor?

• 4V

• 8V

• 16V

• 10V