Fully Destructive Interference Between Two Sinusoidal Waves of the Same

Multiple Choice

Fully destructive interference between two sinusoidal waves of the same frequency and amplitude occurs only if they:

A) travel in the same direction and are 270 ° out of phase
B) travel in the same direction and are 45 ° out of phase
C) travel in the same direction and are in phase
D) travel in the same direction and are 180 ° out of phase
E) travel in the same direction and are 90 ° out of phase