If the current in a coil is AC, the amplitude of MMF
A. varies with time but not with space
B. varies with space but not with time
C. varies with both space and time
D. doesn’t vary with both space and time
Answer:A
If the current in a coil is AC, the amplitude of MMF
A. varies with time but not with space B. varies with space but not with time C. varies with both space and time D. doesn’t vary with both space and time
Explanation: For AC in the coil, the air-gap MMF wave is time variant but space invariant.