■解答
① \(\displaystyle\frac{Ni}{l}\) ② \(\displaystyle\frac{\mu_0NSi}{l}\) ③ \(-\displaystyle\frac{\mu_0N^2S}{l}\frac{\Delta i}{\Delta t}\)
④ \(\displaystyle\frac{\mu_0N^2S}{l}\) ⑤ \(Li\Delta i\) ⑥ \(\displaystyle\frac{1}{2}LI^2\)
⑦ \(I_2R\) ⑧ \(\displaystyle\frac{I_2-I_1}{I_1}R\) ⑨ \((I_2-I_1)R\)
⑩ \(\displaystyle\frac{1}{2}L(I_2^2-I_1^2)\) ⑪ \(\displaystyle\frac{I_2-I_1}{L}R\) ⑫ \(-\displaystyle\frac{(I_2-I_1)I_2}{I_1L}R\)
