What is a trough ?

What is trough ? What is the difference in wavelength between two troughs ?

A magician during a show makes a glass lens with n = 1.47 disppear in a trough of liquid:-What is the refractive index of the liquid?

A magician during a show makes a glass lens with n=1.47 disappear in a trough of liquid. Refractive index of the liquid is

A magician during a show makes a glass lens with n = 1.47 disppear in a trough of liquid:-Could the liquid be water?

Is it possible to represent a longitudinal wave using crests and troughs ?

A steel ball is floating in a trough of mercuty. If we fill the empty part of the trough with water, what will happen to the steel ball ?

A steel ball is floating in a trough of mercuty. If we fill the empty part of the trough with water, what will happen to the steel ball ?

A steel ball is floating in a trough of mercuty. If we fill the empty part of the trough with water, what will happen to the steel ball ?

What is the type of wave motion in which crests and troughs are formed ?