Optics - Vocab and Interference

What type of interference is shown?

• Constructive

• Destructive

The index of refraction of the thin film (water) is higher than air as shown in Figure above - the reflected ray at the air water boundary will undergo a phase change of ½λ ( or π rad).

• TRUE

• FALSE

At the bottom soap-air interface ( soap film has a higher index of refraction n > 1) there will be a phase change for ray 2.

• TRUE

• FALSE

What is the path difference of the reflected rays traveling through the film?

• 2t

• t/2

• 0

Given the index of refractive for oil and water is 1.40 and 1.33 respectively. Both of the reflected rays have a phase change.

• TRUE

• FALSE

What is the condition for the constructive interference of the thin film shown in figure above?

What is the condition for destructive interference to occur for the soap film shown?

• 2nt = mλ

• 2nt = (m+¼)λ

• 2nt = (m+½)λ

• 2nt = (m+¾)λ

Which waves require a medium (matter) to travel?

• x-ray

• microwave

• sound 

• water

Which letter represents amplitude? (a)  

• A
• B
• C
• D
• E

2. What property of a wave is represented by letter B? (a)  

• A. Wavelength
• B. Amplitude
• C. Speed
• D. Frequency