Answer:
The neutral wire is often confused with ground wire, but in reality, they serve two distinct purposes. Neutral wires carry currents back to power source to better control and regulate voltage. Its overall purpose is to serve as a path to return energy.
The difference between the above velocities is that they exist in opposite direction of each other. or it can be said that they are negative vectors of each other.
answer
option d is the correct answer
explanation
as we know frequency is equal to 1 /t
f= 457 Hz
t=1
SO, 1/457
=0.0022sev