Tag: physics

Consider applying an external voltage to the junction with the the negative terminal connected to the P type material and the positive terminal connected to the N type material. For the P-N junction this would require injecting electrons into the P type material. These electrons would recombine with holes and therefore further deplete the majority charge carriers in the P type semiconductor. 

Zener diode is used as a voltage regulator device because the voltage across the zener diode in reverse bias is constant after reaching certain value i.e. breakdown voltage.

As the current in the zener diode increases, the voltage across the diode remains constant. This voltage will be equal to the zener breakdown voltage

The load current is independent of the source voltage variations and hence remains a constant

The load current is given by $I _L=\dfrac{V _z}{R _L}$ and the zener current is given by $I _z=I _s-I _L$. Thus, if the load resistance decreases, load current increases. This in turn will reduce the zener current 

Reflection is defined as the optical phenomenon where light rays come back after hitting a smooth surface.

Reflection occurs when a light ray bounces back from a barrier.

A ray of light which bounces off the surface of mirror is called reflected ray.

Newton used corpuscular theory to explain reflection and refraction of light. According to Sir Isaac Newton's Corpuscular Theory a luminous body continuously emits tiny, light and elastic particles called corpuscles in all directions. When these particles fall on the retina of the eye, they produce the sensation of vision.