A Single Beam of Coherent Light $\lambda$ = 633 Nm)is Incident on Two Glass Slides,which Are Touching

question 62

Multiple Choice

A single beam of coherent light ( $\lambda$ = 633 nm) is incident on two glass slides,which are touching at one end and are separated by a 0.0240-mm thick sheet of paper on the other end.The slides are 6.5 cm long.The beam is split into two beams,with the first reflecting off the bottom surface of the top slide and the second reflecting of the top surface of the bottom slide.You may assume that all the beams are perfectly vertical and that they are perpendicular to both slides,i.e.,the slides are nearly parallel.Both beams recombine above the slides.How many bright bands are observed along the length of the slides?

• A)25
• B)50
• C)75
• D)100
• E)125

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Definitions:

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