A.電場(chǎng)力把單位負(fù)電荷從A點(diǎn)移到B點(diǎn) B.電場(chǎng)力把單位正電荷從A點(diǎn)移到B點(diǎn) C.電場(chǎng)力把單位正電荷從B點(diǎn)移到A點(diǎn) D.洛侖茲力把單位正電荷從A點(diǎn)移到B點(diǎn)
A.增大 B.減小 C.不變 D.不能確定
A.超前Π/4rad B.滯后3Π/4rad C.滯后Π/4rad D.超前3Π/4rad