question_answer

White light may be considered to be a mixture of waves with \[\lambda \] ranging between 3900 A and 7800 A. An oil film thickness 10,000 A is examined normally by the reflected light. If \[\mu \] = 1.4, then the film appears bright for

A)  \[4308\text{ }\overset{o}{\mathop{A}}\,,\text{ }5091\text{ }\overset{o}{\mathop{A}}\,,\text{ }6222\text{ }\overset{o}{\mathop{A}}\,\]           

B)  \[4000\text{ }\overset{o}{\mathop{A}}\,,,\text{ }5091\text{ }\overset{o}{\mathop{A}}\,,,\text{ }5600\text{ }\overset{o}{\mathop{A}}\,,~\]

C)  \[4667\text{ }\overset{o}{\mathop{A}}\,,,\text{ }6222\text{ }\overset{o}{\mathop{A}}\,,,\text{ }7000\text{ }\overset{o}{\mathop{A}}\,\]           

D)  \[4000\text{ }\overset{o}{\mathop{A}}\,,\text{ }4667\text{ }\overset{o}{\mathop{A}}\,,\text{ }5600\text{ }\overset{o}{\mathop{A}}\,\]