Frequency is how many waves passes a certain point in a second and speed is how fast the wave is travelling. Surely this means they are directly proportional as if the speed is high that means lots of waves are passing a point in a certain amount of time ie frequency is larger?
And so looking at the wave equation
V= f x wavelength
how can frequency ever remain constant when speed increases. And so when looking at refraction, my textbook says that when the speed of a wave increases and frequency is constant, wavelength increases. How is it possible for frequency to remain constant?