Question

1. What is light? 2. What are the three models of light? 3. When is each model of light applicable? 4. What is visible light? 5. What is white light? 2-3 sentences each.

Answer 1

1. Light is a form of energy

2. Light can be explained in three models

a. rays , travels in straight lines withiout any bending, applicable to most of the optical instruments like lenses, projectors , movies where light used for visible purpose.

b. Light is a form of electromagnetic wave having both electric and magnetic fields and it is the field energy that transmits in vaccume or in a medium. It is applicable to explain the form of interference and diffraction where the light waves bend at the edges of objects.

c. Light is a form of energy packets called photons. the photons behave like quantum particle. This form of light model is is useful in expliang the phenomina at atomic levels such as absorption and emission spetral lines.

4. Visisble light that aprt of the larger electromagnetic spetrum, which is sensitive to human eye. It range approximately from 300 to 700 nm

5. white light is a compbination of several wave lengths in the visible region of the electromagnetic spectrum. It has contuous wave lenghts from the lower ened of the spectrum to the upper end.