Advertisements
Advertisements
Question
The diagram alongside shows the refraction of a ray of light from air to a liquid.
- Write the values of (i) angle of incidence, (ii) angle of refraction.
- Use Snell’s law to find the refractive index of liquid with respect to air.
Advertisements
Solution
(a) (i) Angle of incidence is the angle which the incident ray makes with normal.
∠i = 90° - 30° = 60°
(ii) The angle that the refracted beam creates with the normal is known as the angle of refraction.
∠r = 90° - 45° = 45°
(b) liquid's refractive index in relation to air.
μ Liquid = `sin i/sin r`
= `(sin 60°)/(sin 45°)`
= `(sqrt3/2)/(1/sqrt2)`
= `sqrt3/2 xx sqrt2`
= `(sqrt3 xx sqrt2)/(sqrt2 xx sqrt2)`
= `sqrt(3/2)`
APPEARS IN
RELATED QUESTIONS
When rays of light are incident on a glass slab then the incident ray and emergent ray are _________ each other.
- perpendicular
- parallel
- opposite
- concurrent
If the speed of light in vacuum is 3 × 108 ms−1, find the speed of light in a medium of absolute refractive index 1.5.
How must light travel out of a substance if it is not going to be refracted?
Draw diagrams to show the refraction of light from
- air to glass, and
- glass to air. In each diagram, label the incident ray, refracted ray, the angle of incidence
- and the angle of refraction (r).
With the help of diagram of the principal section of a prism, indicate its refracting surfaces, refracting edge and base.
Fill in the blanks to complete the following sentence
When light travels from a denser to a rarer medium, its speed ……………….
Rahim recorded the following sets of observations while tracing the path of a ray of light passing through a rectangular glass slab for different angles of incidence.
|
S. No. |
Angle of incidence |
Angle of refraction |
Angle of emergence |
|
I |
45° |
41° |
45° |
|
II |
40° |
38° |
38° |
|
III |
45° |
41° |
40° |
|
IV |
41° |
45° |
41° |
The correct observation is recorded at serial number:
(1) I
(2) II
(3) III
(4) IV
Draw an í- `delta` graph for a mono chromatic raY through a glass prism of a plane and mark
(i) `delta` m, the angle of mínimum devíation
(íí) Any two values of i for which value of `delta` ís same.
How will you verify the laws of refraction or how the refractive index of glass is determined in the laboratory?
A coin placed at the bottom of a beaker appears to be raised by 4.0 cm. If the refractive index of water is 4/3, find the depth of the water in the beaker.
