Resistance of Wire

A wire has a resistance of 10 ohms. What happens to the resistance when the wire is cut into half.

• increases to 20 ohms

• remains the same at 10 ohms

• decreases to 5 ohms

Which wire has the lowest resistance?

• long and thick wire

• long and thin wire

• short and thick wire

• short and thin wire

• A

• B

• C

• D

Which factor does NOT affect the resistance of a wire?

• Length of the wire

• Material of the wire

• Color of the wire

• cross-sectional area of the wire

A wire has a cross-sectional area of 2 mm² and length 2m. The resistance of the wire is 20 ohms.

Calculate the resistance of another wire which is made of the same material and of the same length but with a cross-sectional area of 1 mm².

• 10 ohms

• 20 ohms

• 40 ohms