Young’s double-slit apparatus problem

[AFG34]

[SOLVED] question about light

Homework Statement

True or False question
5. If a Young’s double-slit apparatus, having operated in
air, were to be submerged in water, the fringe pattern
would become less spread out.

Homework Equations

c=f(lamda)

The Attempt at a Solution

What i think they mean: does the wavelength become shorter when light is traveling in a slower medium?

What i don't know is does the frequency of light stay constant regardless of the medium?
If yes, then the statement is true.

 

[G01]

Yes, the frequency is constant regardless of medium. The frequency of a wave only depends on the oscillations of the source of the wave.

 

[AFG34]

Thank you.