water column of height 7 cm. If refractive index of water is
1.269
1.286
1.259
1.310
It is given that wave number in 6cm of glass is the same as the wave number in water with height 7 cm.
Let is wavelength of light in glass and is wavelength of light in water.
According to question,
Also we know that relation between refractive index and wavelength,
Putting values,
Option (2) is correct