Sara asked in Science & MathematicsPhysics · 1 decade ago

What is the angular spread of the beam after passing through the prism?

A narrow beam of light with wavelengths from 450 nm to 700 nm is incident perpendicular to one face of a 31.00degrees prism made of crown glass, for which the index of refraction ranges from n=1.533 to n= 1.517 for those wavelengths.

Explain please

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  • 1 decade ago
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    0.763 degrees.

    You have to solve the prism equation (ref.) for each of the two values of N, and take the difference of the exit angles.

    exit angle = arcsin(N*sin(alpha - arcsin(sin(theta1)/N))), where alpha is the prism apex angle = 31 deg and theta1 is the incidence angle = 0 deg.

    Solving,

    for N = 1.517, exit angle = 51.3809280745386 deg

    for N = 1.533, exit angle = 52.143792690147 deg

    The difference = 0.7628646156084 deg

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  • Wendy
    Lv 4
    4 years ago

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