This chapter explores the properties of light, the formation of shadows, and the phenomenon of reflection. Light is a form of energy that enables us to see objects.
Light travels in straight lines, and it can be reflected, refracted, or absorbed by different materials.
Sources of light include natural sources such as the Sun and artificial sources such as light bulbs and lamps.
Shadows are formed when light is blocked by an opaque object, creating an area of darkness behind the object. Shadows change in size and shape depending on the position and distance of the object from the light source. Different parts of a shadow include the umbra (the darkest part) and the penumbra (the partially shaded part).
Reflection occurs when light bounces off a surface, allowing us to see objects. Polished or smooth surface reflects light better than a rough or dull surface.
Different types of mirrors: plane mirrors and curved mirrors.
Laws of reflection state that the angle of incidence (the angle at which light strikes a surface) is equal to the angle of reflection (the angle at which light bounces off the surface).
Regular reflection occurs when light is reflected in a single direction, such as in a mirror. Diffuse reflection occurs when light is reflected in different directions, such as on a rough surface.
Practical applications of reflection in our daily lives are in mirrors, telescopes, and periscopes.