48. 一矩形電路含一電阻R，以速率v向右移動，遠離通有電流I0的長直導線，如右圖。則矩形迴路之感應電動勢與x之函數關係為何？

6. Given that the enthalpy required to convert CHCl3(g) to gaseous C, H, and Cl atoms is 1397 kJ/mol and that the dissociation enthalpy of a C-H bond is 413 kJ/mol, what is the bond dissociation enthalpy of a C-Cl bond？ (A)328 kJ/mol　(B)603 kJ/mol　(C)984 kJ/mol　(D)1397 kJ/mol