Ohm

A water heater has a resistance of 22 Ω connected to a 220-V voltage source. What is the needed current to operate the heater?

• 5 A

• 7 A

• 8 A

• 10 A

Tags

NGSS.HS-PS2-5

What unit is used to measure resistance?

• Ohms

• Omega

• Volts

• Amps

What is the resistance of a lightbulb that experiences 9 Volts and 3 amps of current?

• 1/3 ohms

• 3 ohms

• 27 ohms

• 9 ohms

What is the voltage of a circuit with 4 ohms of resistance and 3 amps of current?

• 12 V

• 21 V

• 4/3 V

• 3/4 V

How do you calculate voltage?

• Current X Resistance

• Resistance ÷ Current

• Current ÷ Resistance

• Measure it with a ruler

What is resistance measured in?

• Ω (ohm)

• V (volt)

• A (ampere)

• W (watt)

An alarm clock draws 0.5 A of current when connected to a 120 volt circuit. Calculate its resistance.

• 60Ω

• 120Ω

• 180Ω

• 240Ω

Speakers need a household voltage of 110 V to push a current of 5.5 A through them. What is the resistance of the speakers?

• 10Ω

• 20Ω

• 30Ω

• 40Ω

An IPod uses a standard 1.5 V battery. How much resistance is in the circuit if it uses a current of 0.01A?

• 50Ω

• 100Ω

• 150Ω

• 200Ω

What current flows through a hair dryer plugged into a 120 Volt circuit if it has a resistance of 25 ohms?

• 2.4A

• 3.6A

• 4.8A

• 6A