A surveyor is using a magnetic compass 6.4 m below a power line in which there is a steady current of 120 A. (a) What is the mag
netic field in microteslas at the site of the compass due to the power line? (b) Will this field interfere seriously with the compass reading? The horizontal component of Earth’s magnetic field at the site is 20 µT.
If the two waves have the SAME FREQUENCY and are exactly out of phase (180° apart), then the resultant wave will have the same frequency and an amplitude of 1 unit.
If the two waves do not have the SAME FREQUENCY, then their relative phase is meaningless.