Home › CBSE Class 12 (Science) › Physics › Current Electricity › A wire has its length doubled with the same cros…
A wire has its length doubled with the same cross-section and material. What happens to its resistance?
AIt is halved
BIt is doubled
CIt is quadrupled
DIt is unchanged
Answer & Solution
Correct answer: B. It is doubled
Resistance R = rho l / A is proportional to length, so doubling l doubles R.
Related questions
Why is a Wheatstone bridge used with strain gauges?The electrical resistance of a strain gauge is proportional to which quantity?The ratio arms P and Q of a post office box contain which set of resistance values?A post office box is a practical form of which instrument?Which is NOT needed for potential to vary linearly along a potentiometer wire?On a potentiometer wire with steady current, potential difference is proportional to what?Potential gradient along a potentiometer wire is defined as the potential difference per wAn ideal voltmeter should have what value of resistance?