Light moving from a denser to a less dense medium bends in which direction relative to the normal?

Light moving from a denser to a less dense medium bends in which direction relative to the normal?

• A. Toward the normal
• B. Away from the normal
• C. Along the normal
• D. No bending

Answer: (B)

When light moves from a denser to a less dense medium, its speed increases, so the refracted ray bends away from the normal. This follows Snell’s law: n1 sin θ1 = n2 sin θ2. Since the first medium has a higher refractive index (n1 > n2), the ratio n1/n2 is greater than 1, requiring sin θ2 to be larger than sin θ1. That makes the refracted angle θ2 larger than the incident angle θ1, i.e., the ray moves farther from the normal. If the light were entering a denser medium, it would bend toward the normal; if the incidence is along the normal, there’s no bending at all.

When light moves from a denser to a less dense medium, its speed increases, so the refracted ray bends away from the normal. This follows Snell’s law: n1 sin θ1 = n2 sin θ2. Since the first medium has a higher refractive index (n1 > n2), the ratio n1/n2 is greater than 1, requiring sin θ2 to be larger than sin θ1. That makes the refracted angle θ2 larger than the incident angle θ1, i.e., the ray moves farther from the normal. If the light were entering a denser medium, it would bend toward the normal; if the incidence is along the normal, there’s no bending at all.