Ohm's Law

Ohm's Law states that:

• Current = Voltage x Resistance

• Resistance = Voltage x Current

• Power = Voltage x Current

• Voltage = Current x Resistance

A device has a resistance of 12Ω and requires 0.5A of current. What voltage is needed to operate the device?

• 24V

• 6V

• 2.4V

• 0.04V

If a circuit contains a light bulb with a resistance of 30Ω and a 6V battery is used, what will the current be?

• 5A

• 180A

• 1.8A

• 0.2A

According to Ohm's Law, if you were to triple the voltage of a circuit without changing the resistance, what would happen to the flow of current?

• It would stay the same

• It would increase by 2x

• It would increase by 3x

• It would decrease by 3x

Tags

CCSS.8.EE.C.7B

According to Ohm's Law, if you were to double the voltage and double the resistance, what would happen to the flow of current?

• It would stay the same

• It would increase 2x

• It would increase 4x

• It would decrease 2x

Tags

CCSS.8.EE.C.7B

A toy has a 3V battery that produces a 0.2A of current. What is the toy's resistance?

• 0.6Ω

• 15Ω

• 0.07Ω

• 6Ω

A circuit breaker is set to trip if current above 15A is detected in the circuit. A toaster oven and microwave are both plugged into the same kitchen circuit and each run on 8A of current. What will happen if someone tries to use the microwave?

• The circuit breaker will always trip

• The circuit breaker will trip only if the toaster oven is in use at the same time

• The circuit breaker will trip only if the dishwasher is running on a different circuit

• The circuit breaker will never trip

In our water tank analogy for electricity, what did the tank of water (see arrow) represent?

• Voltage

• Power

• Current

• Resistance

Imagine you are testing an electrical toy. It gets plugged into a home outlet, which has an electrical potential difference of 120V. The wires are small and you do not want the current to go above 1.5A. How high must the toy's resistance be?

• 180Ω

• 60Ω

• 0.0125Ω

• 80Ω

Which of the following is NOT a correct form of Ohm's Law?

• V = IR

• I = R/V

• R = V/I

• I = V/R