The refractive index of a piece of glass of `1.5`and it acomodates as many waves as are accomodated in`18cm` width of water column.If the refractive index of water `1.33`then the thickness of glass piece will be-
A. `20cm`
B. `10cm`
C. `12cm`
D. `16cm`
A. `20cm`
B. `10cm`
C. `12cm`
D. `16cm`
Correct Answer – 4
`n_(glass)=1.5`
`N_(water)=1.33`
`t_(water)=18cm`
`t_(glass)=?`
`:.n_(glass)t_(glass)=n_(water)t_(water)…….(1)`
Fromeqs.(1)and(2) …….. (2)
`t_(glass)=(1.33xx18)/(1.5)=16cm`