If two waves have equal amplitudes, the phase difference between them refers to the relative shift in their starting points or positions along the horizontal axis (time axis) or circular axis (in the case of waveforms represented in a polar coordinate system).
For example, let's consider two sine waves with equal amplitudes. A sine wave can be represented by the equation:
y = A * sin(ωt + φ)
In this equation, A represents the amplitude, ω represents the angular frequency (2π times the frequency), t represents time, and φ represents the phase.
If two sine waves have equal amplitudes, their amplitudes (A) would be the same. The phase difference (Δφ) between the two waves can be calculated by subtracting the phase of one wave from the phase of the other wave.
Δφ = φ2 - φ1
If the phase difference is 0, it means the two waves are in phase and start at the same position. If the phase difference is π radians (180 degrees), it means the waves are completely out of phase and start at opposite positions.
In summary, for two waves with equal amplitudes, the phase difference can vary between 0 and 2π radians (or 0 and 360 degrees) depending on their relative starting positions.