Answer:
very low air pressure and that's not 100 points
Answer:
The less energy a wave has, the smaller the amplitude
Explanation:
Hope this helps!!!
When. the train approaches you, the wavelength of the sound waves it emits are compressed, and therefore the whistle sounds higher.
But When the train is moving away, the wavelengths are extended, causing the whistle to sound lower. It's called the Doppler effect.
The answer should be 0.2 :D
