What can be found by counting the number of troughs per second in a wave diagram
amplitude
direction
frequency
speed
wavelength

Respuesta :

frequency,................

Answer: By counting the number of troughs per second frequency can be calculated.

Explanation:

Frequency of the wave is defined as number of cycles occurring in one second. By counting the number of troughs per second we can calculate frequency of the wave

Amplitude of the wave is defined as maximum displace of the particle from its means position is known as Amplitude.

Wavelength of the wave is defined as distance between two successive  crests or troughs.