Question

A plane glass plate is placed over a various coloured letters (violet, green, yellow, red). The letter which appears to raised more 

(1) Yellow 

(2) Violet 

(3) Red 

(4) Green

Answer 1

Correct option (2) Violet    

Explanation:

S_N = t (1-1/h) As n increases, 1/h decreases and (1- 1/h) increases.

∴  S_N is more for that colour, for which n is more

Among the given colours n is more for violet. 

Therefore it appears to be raised more.