If the length of a wire is doubled while keeping the cross-sectional area consta
Practice Questions
Q1
If the length of a wire is doubled while keeping the cross-sectional area constant, how does its resistance change?
Remains the same
Doubles
Halves
Quadruples
Questions & Step-by-Step Solutions
If the length of a wire is doubled while keeping the cross-sectional area constant, how does its resistance change?
Correct Answer: Resistance doubles.
Step 1: Understand that resistance is a property of a wire that affects how easily electricity can flow through it.
Step 2: Know that resistance (R) is directly related to the length (L) of the wire. This means that if you increase the length, the resistance increases.
Step 3: If the length of the wire is doubled, it means you have a wire that is twice as long as before.
Step 4: Since resistance is directly proportional to length, if you double the length of the wire, you also double the resistance.
Step 5: Therefore, if the original resistance was R, the new resistance after doubling the length will be 2R.
Ohm's Law – Resistance (R) is directly proportional to the length (L) of the wire, given by the formula R = ρ(L/A), where ρ is resistivity and A is cross-sectional area.