Bissoy.com
Doctors Medicines MCQs Q&A

Refraction from denser to rare medium for a light ray, the value of angle of refraction at the condition of critical angle is

Refraction from denser to rare medium for a light ray, the value of angle of refraction at the condition of critical angle is Correct Answer 90°

Ans: Option 3)

CONCEPT:

  • Refraction: When a ray of light bounces back from a surface, then it is called a reflection of light.
  • Refraction: When a ray of light or wave passes from one medium to another, it deviates from its original path. This deviation is called refraction.
  • Critical angle: It is the angle of incidence within the denser medium like which the angle of refraction within the rarer medium is 90°.

EXPLANATION: 

  • When a light ray travels from denser medium to rarer medium, at a certain angle of incidence, the angle of refraction becomes 90°. The angle of incidence at this point is called a critical angle.

Additional Information

  • When the refracted ray bounces back again in the same medium then it is called total internal reflection.
  • i.e., The angle of refraction is greater than 90°. 

Related Questions

A ray of light travels from air to water as shown below. What are ray PQ and ray PR?   Ray PQ Ray PR (A) Reflected ray Refracted ray (B) Reflected ray Reflected ray (C) Refracted ray Refracted ray (D) Refracted ray Reflected ray
Which of the following statement(s) is/are CORRECT for the critical angle? I. Refractive angle is 90o. II. Light ray goes from rarer to denser medium. III. Light ray goes from denser to rarer medium.
Which of the following statement(s) is/ are correct for critical angle?
1. Refractive angle is 90°.
2. Light ray goes from rarer to denser medium.
3. Light ray goes from denser to rarer medium.
Consider the following statement: A ray of light passing through the optical centre of a convex lens emerges without any deviation after refraction. A ray of light passing through the first principal focus of a convex lens  emerges parallel to the principal axis after refraction. A ray of light passing through the optical centre of a convex lens emerges parallel to the principal axis after refraction. Which one of the following statements INCORRECT?
There are two medium L1 and L2 of refractive index n1 and n2 respectively (n2  > n1 > 1). In which of the following condition the total internal reflection may occur: a) When the light travel from medium L1 to medium L2. b) When the light travels from medium L2 to medium L1. c) When the light travel from medium L1 to air. d) When the light travels from air to medium L2. Which of the following statement is correct?
Consider the following statements. i) For a perfect reflection, the angle of incidence will be equal to the angle of reflection. ii) The critical angle is the angle of incidence in the denser medium for which the angle of refraction in the rarer medium is 90°. Which of the above statements are true?
Consider the following statements about visible light, UV light and X-ray.
1. The wavelength of visible light is more than that of X-ray.
2. The energy of X-ray photons is higher than that of UV light photons.
3. The energy of UV light photons is less than that of visible light photons.
Which of the statement(s) given above is/are correct?
Assertion (A): Small glass beads fixed on traffic signals glow brightly when light falls upon them.
Reason (R): Light is totally reflected when the angle of incidence exceeds a certain critical value and light travelling in a denser medium is reflected from a rarer medium.
When a ray of light passes from one medium to another (rarer to denser or denser to rarer), which of the following phenomenon of light is observed?
Choose the correct relation for a combination of two prisms to be achromatic. (Where for the first prism: μv = refractive index of the medium in violet light, μr = refractive index of the medium in red light A = angle of the prism; For the second prism: μ′v = refractive index of the medium in violet light, μ′r = refractive index of the medium in red light, A’ = angle of prism.)