JEE Main 2019 Physics question
A copper wire is stretched to make it 0.5% longer. The percentage change in its electrical resistance if its volume remains unchanged is:
Answer: (D)
Solution
At constant volume R ∝ l ⇒ 2 × 0.5% = 1%.
A copper wire is stretched to make it 0.5% longer. The percentage change in its electrical resistance if its volume remains unchanged is:
At constant volume R ∝ l ⇒ 2 × 0.5% = 1%.