Advertisements
Advertisements
प्रश्न
A rectangular block of glass ABCD has a refractive index 1.6. A pin is placed midway on the face AB (Figure). When observed from the face AD, the pin shall ______.
- appear to be near A.
- appear to be near D.
- appear to be at the centre of AD.
- not be seen at all.
पर्याय
a and c
a and d
b and d
c and d
Advertisements
उत्तर
a and d
Explanation:
As long as angle of incidence on AD of the ray emanating from the pin is less than the critical angle, the pin shall appear to be near A.
When angle of incidence on AD of the ray emanating from pins is greater than the critical angle, the light suffers from total internal reflection and cannot be seen through AD.
APPEARS IN
संबंधित प्रश्न
State the relation between the critical angle and the absolute refractive index of a medium.
Plot a graph between
Angle of incidence versus angle of reflection,
If a light ray does not undergo, refraction at the boundary between two media, the angle of incidence is:
How does a ray of light bend when it travels from rarer to denser medium
A ray of light passes through a right-angled prism as shown in the figure. State the angles of incidence at the faces AC and BC.
Answer the following question.
Define the critical angle of incidence and obtain an expression for it.
Answer the following question.
What are the advantages of optical fibre communication over electronic communication?
Solve Numerical example.
A monochromatic ray of light is incident at 37° on an equilateral prism of refractive index 3/2. Determine angle of emergence and angle of deviation. If angle of prism is adjustable, what should its value be for emergent rays to be just possible for the same angle of incidence?
Observe the given figure and write appropriate phenomenon of light in the box.
What is the phenomenon used in optical fiber? Explain.
A green light is incident from the water to the air-water interface at the critical angle (θ). Select the correct statement.
A ray of light incident at an angle θ on a refracting face of a prism emerges from the other face normally. If the angle of the prism is 5° and the prism is made of a material of refractive index 1.5, the angle of incidence is ______.
A ray of light passes through a prism of refractive index `sqrt2` as shown in the figure. Find:
- The angle of incidence (∠r2) at face AC.
- The angle of minimum deviation for this prism.
A light is entering from one medium refractive index `("RI" =5/3)` to another medium at an angle 30°. The angle of refraction for other medium is sin-1 `(5/6)`. then the increase in angle of incidence is ______ such that the ray of light reflected back into the same medium.
- Assertion (A): Propagation of light through an optical fibre is due to total internal reflection taking place at the core-cladding interface.
- Reason (R): Refractive index of the material of the cladding of the optical fibre is greater than that of the core.
Small air bubbles rising up a fish tank appear silvery when viewed from some particular angle is due to the ______.
The diagram below shows a fish in the tank and its image seen on the surface of the water.
Name the phenomenon responsible for the formation of this image.
State two differences between normal reflection and total internal reflection.
