2nd lesson 8th grade Ohm's law

2nd lesson 8th grade Ohm's law

Example

USB charging cable (1 m long) uses 5 Volts and 2 Amperes. How many ohms is the USB charging cable?

Multiple Choice

If a circuit has a voltage of 500 V and a resistance of 250 Ω, what is the current?

• 1 A

• 2 A

• 3 A

• 4 A

Fill in the Blanks

Multiple Choice

An iron wire has a cross section area of 10 mm² and length of 300 m. What is the resistance of the wire? ρ=10x10^-8 Ohm⋅m

• 1 ohm

• 2 ohm

• 3 ohm

• 4 ohm

Multiple Choice

Which material has more resistance at the same

conditions?

• A

• B

• C

• D