Light of Wavelength 425

question 26

Multiple Choice

Light of wavelength 425.0 nm in air falls at normal incidence on an oil film that is 850.0 nm thick.The oil is floating on a water layer 15 cm thick.The refractive index of water is 1.33,and that of the oil is 1.40.You want to add oil so that light reflected off of the top of the oil film will be canceled.What is the minimum distance that you should INCREASE the oil film?

• A) 60.7 nm
• B) 75.9 nm
• C) 106 nm
• D) 121 nm
• E) 152 nm

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Definitions:

Intergenerational Group

A group composed of members from different generations, enabling the exchange of knowledge, values, and cultural practices across ages.

Advocates

Individuals who actively support or defend a cause or policy, often on behalf of another person or group.

Helper-therapy Principle

The helper-therapy principle suggests that individuals who assist others in a therapeutic context can also benefit themselves, improving their own well-being through the process of helping.

Group Leader

Someone appointed or emerging within a group to steer its activities and decision-making processes toward collective goals.