Explain how the sun makes shadows throughout the day.
The sun makes shadows throughout the day because it emits light in one direction. When sunlight passes through an object, it causes the object to block or absorb some of the light, creating an area of darkness behind it. This area of darkness is what we refer to as a shadow.
To understand this process, we need to consider the concept of light traveling in straight lines. When the sun emits light rays, these rays spread out in all directions. However, when an object is placed in the path of these rays, it blocks some of them from reaching a particular area. This blockage results in the creation of a shadow on the opposite side of the object.
The size, shape, and position of a shadow are determined by the angle at which the sunlight hits the object and the object's shape and distance from the surface receiving the shadow. If the light source, object, and the receiving surface are in alignment, the shadow created will appear small and crisp. As the angle between the light source, object, and receiving surface changes, the shadow lengthens and becomes less defined.
Throughout the day, the position of the sun changes due to Earth's rotation. As a result, the angle at which sunlight hits objects in the environment changes, and therefore, the position and length of the shadows also change. Shadows are shortest when the sun is directly overhead (at noon) because the light rays are more perpendicular to objects, resulting in less elongation. As the sun moves closer to the horizon (during sunrise or sunset), the angle of the light rays becomes more oblique, causing shadows to lengthen.
Thus, the movement of the sun across the sky during the day, combined with the interaction of light with objects, results in the continuous creation and changing positions of shadows.