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Question 29

In order for fibre optics to work, the incident light inside it must hit its wall at

  • A.90°
  • B.an angle greater than the critical angle
  • C.45°
  • D.an angle lesser than the critical angle
Objective

Question details

Exam body
NDA
Subject
Physics
Year
2019/2020
Question no.
#29
Type
Objective
Previous · Q28Which of the following statements about a diode is correct? Next · Q30 In the earth's gravitational field.

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