You are standing in air and looking at a flat piece of glass. If a light ray passes from air into the glass at an angle, which of the following correctly describes how the light ray will bend according to $Snell’sLaw$?

• A. The light ray will bend toward the normal as it enters the glass.
• B. The light ray will bend away from the normal as it enters the glass.
• C. The light ray will continue in a straight line without bending.
• D. The light ray will reflect completely back into the air.

Answer: (A)

Verified step by step guidance

1. Identify the two media involved: air and glass. Air has a lower refractive index (n₁) compared to glass (n₂), meaning n₁ < n₂.
2. Recall Snell's Law, which relates the angles and refractive indices of the two media: \(n_1 \sin{\theta_1} = n_2 \sin{\theta_2}\), where \(\theta_1\) is the angle of incidence in air and \(\theta_2\) is the angle of refraction in glass.
3. Since the light is moving from a medium with lower refractive index (air) to a higher refractive index (glass), the sine of the refracted angle must be smaller to satisfy Snell's Law, implying \(\theta_2 < \theta_1\).
4. A smaller refracted angle means the light ray bends toward the normal line when entering the glass from air.
5. Therefore, according to Snell's Law, the correct description is that the light ray bends toward the normal as it enters the glass.