Final answer:
When light passes from one material to another where its speed is lower, it bends towards the normal due to refraction, making the angle of refraction smaller than the angle of incidence (θ2 < θ1).
Step-by-step explanation:
When light passes at an angle to the normal from one material into another material in which its speed is lower, the behavior of light can be described by the principles of refraction. According to these principles, specifically Snell's Law, the light ray bends towards the normal when entering a medium where it travels slower.
Understanding Refraction
A key concept in optics is the refractive index, a measure indicating how much a substance can bend the light. Snell's Law states that n1 sin(θ1) = n2 sin(θ2), where n1 and n2 are the refractive indices of the two media, and θ1 and θ2 are the angles of incidence and refraction respectively. In this case, since light is entering a medium where its speed decreases, the refractive index of the second medium is higher, and the light bends towards the normal; therefore, θ2 becomes smaller than θ1 (θ2 < θ1).