what is the frequency that affects dogs the most?

Answer 1

The number of vibrations that are produced per second is called frequency. Frequency varies for each sound and is measured in hertz. One hertz is equal to one vibration per second.
Dogs hear high tones in particular much better than humans do. Humans can pick up an average of 20,000 acoustic vibrations per second (kHz), whereas a dog is able to perceive between 40,000 and 100,000 vibrations. A dog whistle is around 45,000 kHz.