Home
Class 12
PHYSICS
Assertion (A) : When tiny circular obsta...

Assertion (A) : When tiny circular obstacle is placed in the path of light from some distance, a bright spot is seen at the center of the shadow of the obstacle.
Reason (R ) : Destructive interference occurs at the centre of the shadow.

A

If both assertion and reason are true and the reason is the correct explanation of the assertion

B

If both assertion and reason are true but reason is not the correct explanation of the assertion

C

If assertion is true but reason is false.

D

If the assertion and reason both are false

Text Solution

Verified by Experts

The correct Answer is:
C

As the waves diffracted from the edges of circular obstacle, placed in the path of light interfere constructively at the centre of the shadow resulting in the formation of a bright spot.
Promotional Banner

Topper's Solved these Questions

  • WAVE OPTICS AND ELECTROMAGNETIC THEORY

    ERRORLESS|Exercise PAST YEARS QUESTIONS|45 Videos
  • RAY OPTICS

    ERRORLESS|Exercise Assertion & Reason|30 Videos

Similar Questions

Explore conceptually related problems

A: When a tiny circular obstacle is placed in the path of light from a distant source, a bright spot is seen at the centre of the shadow of the obstacle. R: Waves diffracted from the edge of the circular obstacle interfere constructively at the centre of the shadow producing a bright spot.

Answer the following questions (a) In a single slit diffraction experiment, the width of the slit is made double the original width. How does this affect the size and intensity of the central diffraction band? (b) In what way is diffraction from each slit related to the interference pattern in a double-slit experiment? (c) When a tiny circular obstacle is placed in the path of light from a distant source, a bright spot is seen at the centre of the shadow of the obstacle. Explain why? (d) Two students are separated by a 7 m partition wall in a room 10 m high. If both light and sound waves can bend around obstacles, how is it that the students are unable to see each other even though they can converse easily (e) Ray optics is based on the assumption that light travels in a straight line. Diffraction effects (observed when light propagates through small apertures/slits or around small obstacles) disprove this assumption. Yet the ray optics assumption is so commonly used in understanding location and several other properties of images in optical instruments. What is the justification?

Interference fringes were produced using light in a doulbe-slit experiment. When a mica sheet of uniform thickness and refractive index 1.6 (relative to air) is placed in the path of light from one of the slits, the central fringe moves through some distance. This distance is equal to the width of 30 interference bands if light of wavelength 4800 is used. The thickness (in mu m ) of mica is

A man running along a circular track has the speedof 10 km per hour. A source of light is at the centre of the circular track. A wall is along the tangent to the circular track at the point from which he starts.What is the speed of the shadow of the man on the wall when he covers 1/8th of the track? (Assume thetrack to be a line.)

ERRORLESS-WAVE OPTICS AND ELECTROMAGNETIC THEORY-ASSERTION & REASON
  1. Assertion (A) : The unpolarised light and polarized light can be disti...

    Text Solution

    |

  2. Assertion: Nicol prism is used to produce and analyse plane polarised ...

    Text Solution

    |

  3. Assertion: In everyday life to Doppler's effect is observed readily fo...

    Text Solution

    |

  4. Statement I: In Young's experiment, the fringe width for dark fringes ...

    Text Solution

    |

  5. Assertion: Coloured spectrum is seen when we look through a muslim clo...

    Text Solution

    |

  6. Assertion (A) : When tiny circular obstacle is placed in the path of l...

    Text Solution

    |

  7. Statement I: Thin films such as soap bubble or a thin layer of oit on ...

    Text Solution

    |

  8. Assertion : Corpuscular theory fails to explain the velocities of ligh...

    Text Solution

    |

  9. Assertion (A) : Interference pattern is made by using blue light inste...

    Text Solution

    |

  10. Assertion : The clouds in the sky generally appear to be whitish. Re...

    Text Solution

    |

  11. Why is it necessary to use satellites for long distance TV transmissio...

    Text Solution

    |

  12. Assertion: The pattern and position of fringes always remain same even...

    Text Solution

    |

  13. Assertion: In Hertz experiment, the electric vector of radiation produ...

    Text Solution

    |

  14. Assertion: For cooking in a microwave oven, food is always kept in met...

    Text Solution

    |

  15. Assertion: X-ray astronomy is possible only from satellites orbiting t...

    Text Solution

    |

  16. Assertion: Ultraviolet radiation are of higher frequency waves are dan...

    Text Solution

    |

  17. Assertion: Environment damage has increased the amount of ozone in the...

    Text Solution

    |

  18. Assertion: Radio waves can be polarised. Reason: Sound waves in air ...

    Text Solution

    |

  19. Assertion : The earth without its atmosphere would be inhospitably col...

    Text Solution

    |

  20. Assertion: Like light radiation, thermal radiations are also electroma...

    Text Solution

    |