Summary
Highlights
Reflection occurs when light rays bounce off an object. Smooth and shiny surfaces like mirrors, metal, and glass are good reflectors. A line perpendicular to the surface, called the normal, can be drawn at the point of incidence where light reflects.
Light travels in a straight path until it interacts with an object. Upon contact, light rays can be absorbed, reflected, or refracted. These are the three primary ways light interacts with matter.
Refraction happens when light rays pass from one medium to another and change direction because their speed changes. This causes objects to appear distorted, as seen when light moves from air to water or glass. Examples of objects that refract light include prisms, microscopes, glasses, telescopes, and camera lenses.
Light absorption occurs when an object takes in light rays. For example, a car exposed to sunlight absorbs some light, making it hot. Darker objects absorb more light than lighter objects like white ones, which tend to reflect more light.
Rainbows are a natural phenomenon that combines both refracted and reflected light. Similarly, when looking into a lake, some light rays are refracted as they enter the water, while others are reflected off the surface, allowing for both distorted underwater views and reflections.
In review, light always travels in a straight path but can be reflected off objects like mirrors, refracted when passing from one medium to another (e.g., air to water), or absorbed by objects. Darker objects absorb more light energy than lighter ones.