Answer
Answer
Answer
rectiliner propagation
Light rays traveling through air or a vacuum demonstrate rectilinear propagation as they travel in a straight line. Sound waves can also exhibit rectilinear propagation in a homogeneous medium, as long as there are no obstructions or obstacles that cause the wavefront to bend or diffract.
"Umbra" means "shadow"; specifically the darkest part of the shadow of a planet or moon during an eclipse.
A shadow is created when an object blocks light, causing a dark area to form behind it. The size and shape of the shadow depend on the angle of the light source, the distance between the object and the surface where the shadow falls, and the properties of the object itself. Other factors that influence shadow formation include the intensity and direction of the light, as well as the presence of other objects that may also block or reflect light.
Three essential conditions for shadow formation are a source of light, an object to block the light, and a surface to project the shadow onto. When light is blocked by an object, it creates an area behind the object where light cannot reach, resulting in a shadow being cast on the surface opposite the light source.
Shadows are created when an object blocks light, causing a dark area to form behind it. Factors that influence shadow formation include the angle of the light source, the size and shape of the object, and the distance between the object and the surface where the shadow is cast.
That light cannot pass through some materials, and that this leads to the formation of shadows.
an opaqe objecta sorce of light
L.L Brunk wrote Between Shadow & Light.
It is a dance sort of like ballroom dancing. It is a pattern or a sort of shadow by a group of people.