Movement of Light

Movement of Light

The properties of light is that it moves straight, can be reflected and can be refracted. Light is very important because it allows us to see the environment. These properties of light also provide many benefits to humans through various applications.

5.1

Movement of Light

Light travels from a light source in a straight line

Examples of situations where light moves in a straight line

Sunlight radiated through the trees

Spotlights on stage

Shadow clarity of object

Shadows are formed when a moving light is obstructed by an object
The clarity of the formed shadow varies according to the type of object that obstructs it, either:

Transparent
Translucent
Opaque

Transparent is a characteristic of an object (for example, clear plastic) that allows all light to pass through it
Translucent is a characteristic of an object (for example, colored plastic) that allows some light to pass through it
Opaque is a characteristic of an object (for example, a manila card) that does not allow light to pass through it

Factors affecting the size of shadows

Two factors affect the size of the shadow

Distance between an object with the light source
Distance between an object with the screen

The longer the distance between the object and the light source, the smaller the size of the shadow.
The longer the distance between the object and the screen, the bigger the size of the shadow.

Factors affecting the shape of shadows

The position of the light source makes the shape of the shadow different
The position/orientation of the object can also be changed to produce different shapes of shadows