If a certain piece of copper is to be shaped into a conductor of minimum resistance, it is length (L) and cross-sectional area (a) shall respectively be :
Correct answer: B. L/2, 2A
- A. L, 2A
- B. L/2, 2A
- C. 2L, 2A
- D. 2L, A/2
Explanation
b) L/2, 2A This option suggests that to minimize resistance, the length (L) of the copper piece should be halved (L/2), and the cross-sectional area (a) should be doubled (2A). This is the correct option. Minimizing resistance involves increasing the cross-sectional area of the conductor while reducing its length. This option achieves the proper balance between length and cross-sectional area to minimize the resistance.
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