Question 11
Circle the correct answer.
When a light ray travels from glass into air, its speed (decreases / increases) because the optical density of air is (lower / higher) than the optical density of glass. This change in speed causes the light to change (brightness / direction).
When a light ray travels from glass into air, its speed (decreases / increases) because the optical density of air is (lower / higher) than the optical density of glass. This change in speed causes the light to change (brightness / direction).
