Q.

Light travels a distance x in time t1 in air and 10x in time t2 in another denser medium. What is the critical angle for this medium            [2023]
 

1 sin-1(t110t2)  
2 sin-1(10t1t2)  
3 sin-1(t2t1)  
4 sin-1(10t2t1)  

Ans.

(2)

For air, c=xt1

For medium, v=10xt2  ;  μ=cv=x×t2t1×10x=t210t1

sinC=1μ=10t1t2  ;  C=sin-1[10t1t2]