what is the difference between source light and reflected light?

Answer 1

Source light is light that is coming directly from the source (light bulb, sun, etc).

Reflected light is light that is coming from a surface that is bouncing the light back out.

So you shine a flashlight on a mirror. The beam from the light to the mirror is source light and the light reflecting off the mirror is the reflected light.

Answer 2

We observe our surroundings through the reflection of visible light, emitted by our Sun or man-made sources. Source light is composed of photons generated by the matter emitting the light - it's an intrinsic source of light. Reflected light consists of photons whose origin is elsewhere but reflected from some object. Light falling upon matter can be absorbed, reflected, or transmitted (meaning that the light and matter interact very little - the matter is transparent), or often some combination.

Answer 3

Objects which emit light are called luminous objects and which reflect or disperse light are called non-luminous objects.

In general by a source of light we mean a source of luminous object.

However, a source of light can be anything from which we receive light.

Reflected light is the light that we receive after a light from a luminous object is reflected from a non luminous object. A reflected may further be reflected from another non-luminous object and in that case also we call it as reflected ray.

THE PROPERTIES OF LIGHT ONCE EMITTED FROM A LUMINOUS OBJECT DO NOT DEPEND UPON THE OBJECT AFTER EXIT FROM IT.

Therefore, one never bothers whether a light is coming from a non luminous object or from a luminous object.

The point which we consider for our purpose as the starting point of light is the source of light.

If light from a luminous source of light falls on a slit, then the slit is considered as the source of light. If it falls on two slits then these two slits are considered as two sources of light.

Thus we can say for clarity that there are luminous sources of light and non luminous sources of light.

Huygens, in his theory, considered each point of a wave front of light as secondary sources of light.
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