Physics – A thin film of oil (n = 1.26) is located on smooth

Physics – A thin film of oil (n = 1.26) is located on smooth

Subject: Physics    / General Physics
Question

A thin film of oil (n = 1.26) is located on smooth, wet pavement.

When viewed from a direction perpendicular to the pavement, the film reflects most strongly red light at 640 nm and reflects no light at 512 nm. What is the minimum thickness of the oil film?___ nm