//chapter8,Example8_5,pg 182

//since both reflections occur at surface of denser medium

//condition for brightness for min thickness, n=1

//for normal incidence r=0, cos(r)=1

lam=5500*10^-8

V=0.2

A=100*100//converting into cm2

t=V/A

u=lam/(2*t)

printf("RI of oil\n")

printf("u=%.2f",u)