Physics for IGCSE & O level - Waves And Sounds (Section 4 - No. 40)
In the Doppler effect, what happens to the observed frequency if the source of the wave and the observer are moving closer together?
The frequency decreases.
The frequency increases.
The frequency remains the same.
The frequency disappears.
คำอธิบาย
The frequency increases as the source and observer approach each other.