Advertisements
Advertisements
Question
A glass prism is able to produce the spectrum when white light passes through it, but a glass slab doesn’t produce any spectrum. Explain why it is so.
Advertisements
Solution
The two faces of a glass prism are at an angle (angle of prism) with each other. Therefore, the angle of incidence and the angle of emergence of a light ray become different in the case of a prism. Therefore, when white light gets dispersed after entering a prism, its component colours spread more after refracting through the opposite face of the prism.
In the case of a glass slab, the two opposite faces of the slab are parallel to each other. Therefore, the angle of incidence and the angle of emergence of a light ray remain the same for a glass slab. Therefore, the dispersed light rays combine to form white light after refracting through the second face of the glass slab.
APPEARS IN
RELATED QUESTIONS
Draw a ray diagram to explain the term angle of deviation.
Draw a diagram to show how white light can be dispersed into a spectrum by using a glass prism. Mark the various colours of the spectrum.
Which is refracted most by a prism : red light or violet light? Explain why?
Which of the following colour of white light is least deviated by the prism?
(a) green
(b) violet
(c) indigo
(d) yellow
The speed of light in air or vacuum is
What conclusion do you draw about the nature of white light in part (b)?
Draw a labeled ray diagram to illustrate the dispersion of a narrow beam of white light when it passes through a glass prism.
An object is placed in front of a converging lens and in front of a diverging lens as in fig.
(a)Complete the ray diagram to obtain an image.
(b)Compare the nature of image formed by both the lenses in the above case.
A wave has wavelength 50Å of State its one use.
When white light enters a glass prism from the air, the angle of deviation is least for ____________.
