电路如图所示,L=1H,R=1Ω,,则i的有效值为( )。
A <img border="0" alt="" src="https://tuku.weimei168.com/uploads/upimg/20251103/23425401_0_2.png"> B
<img border="0" alt="" src="https://tuku.weimei168.com/uploads/upimg/20251103/23425401_0_3.png"> C
<img border="0" alt="" src="https://tuku.weimei168.com/uploads/upimg/20251103/23425401_0_4.png"> D
1A