問題詳情

13. When a ductile metal wire is stretched to N times its original length (without changing its density and resistivity), the resistance R will change by a factor of
(A) 1/N2；
(B) 1/N；
(C) N；
(D) N2；
(E) None.

參考答案

答案：D
難度：計算中-1
書單：沒有書單，新增