Specular reflection occurs under which condition?

Specular reflection occurs under which condition?

• A. Scattering occurs when the surface is rough.
• B. Diffraction occurs when the aperture is small.
• C. Refraction occurs with oblique incidence.
• D. Specular reflection occurs when the surface is smooth and large.

Answer: (D)

Specular reflection happens when the surface is smooth on the scale of the light’s wavelength and large compared with it. In that case, the reflected waves remain in phase across the surface, so they combine to produce a single, mirror-like image with the angle of reflection equal to the angle of incidence (the law of reflection). If the surface is rough at that scale, different points reflect light in different directions, leading to diffuse reflection where no clear image forms. Diffraction, on the other hand, arises from waves bending around openings or edges, and refraction is the bending of light when it passes into a medium with a different refractive index. So the condition that yields a clear, specular reflection is a smooth, large surface.

Specular reflection happens when the surface is smooth on the scale of the light’s wavelength and large compared with it. In that case, the reflected waves remain in phase across the surface, so they combine to produce a single, mirror-like image with the angle of reflection equal to the angle of incidence (the law of reflection). If the surface is rough at that scale, different points reflect light in different directions, leading to diffuse reflection where no clear image forms. Diffraction, on the other hand, arises from waves bending around openings or edges, and refraction is the bending of light when it passes into a medium with a different refractive index. So the condition that yields a clear, specular reflection is a smooth, large surface.