Question

Question #c742e

Answer 1

The relation between real depth(D) and apparent depth(d) with refractive index of water(n) is given above

So `n=D/d`

Here `n=4/3,d=9m,D=?`

`D=d*n=9xx4/3=12m`

So decrease in percentage of depth due to refraction through water will be

`=(D-d)/Dxx100=(12-9)/12xx100%=25%`

Answer 2

`25%`

Explanation:

If the apparaent depth `(d_a)` of an object of real depth`(d_r)` is found in a media of refractive index `4/3`

Then they are related as,

`d_r = 4/3 d_a`

Given, `d_a =9m`

So, `d_r= 12 m`

So,it is smaller by `(d_r-d_a)/(d_r) * 100 = 3/12 *100 = 25`

So, apparent depth is `25 %` smaller than the real depth