Dispersion of Light in Prisms

Steps:

• Visible light consists of different colors with varying wavelengths; shorter wavelengths correspond to blue light, longer to red.
• When light passes through a prism, it undergoes refraction, bending based on the medium's refractive index.
• The refractive index is higher for shorter wavelengths (blue) than longer ones (red) in most materials, causing dispersion.
• This results in blue light deviating more than red light.

Why D is correct:

• According to Snell's law (n1 sin i = n2 sin r), higher refractive index for blue light causes greater refraction angle compared to red light.

Why the others are wrong:

• A. Blue light has a longer wavelength than red light, so the statement is false.
• B. Blue light has a shorter wavelength than red light, not longer.
• C. In glass, blue light travels slower than red light due to higher refractive index.

Final answer: D