Home
Class 12
PHYSICS
In a two tourmalines experiment, the pol...

In a two tourmalines experiment, the polariser and analyser are crossed with each other. At what angle should the analyser be rotated so that 25% of light passes through analyser ?

A

`60^(@)`

B

`90^(@)`

C

`30^(@)`

D

`45^(@)`

Text Solution

Verified by Experts

The correct Answer is:
C
From Malus law,
`I=I_(0) cos^(2) theta" " [ I=I_(0),25%=(I_(0))/(25)]`
`(I_(0))/(4)=I_(0) cos^(2) theta`
`(1)/(2) cos theta :. theta=60^(@)`
`:.` Analyswer should be rotates at `(90^(@)-60^(@))=30^(@)` angle.
Promotional Banner

Topper's Solved these Questions

  • WAVE OPTICS

    KUMAR PRAKASHAN|Exercise SECTION-C NCERT Exemplar Solution (Long Answer Type Questions)|5 Videos

  • SEMICONDUCTOR ELECTRONICS : MATERIALS, DEVICES AND SIMPLE CIRCUITS

    KUMAR PRAKASHAN|Exercise Section-D : Multiple Choice Questions (MCQs) (MCQs asked in Competitive Exams)|129 Videos

Similar Questions

Explore conceptually related problems

A polariser and an analyser are oriented so that maximum light is transmitted what will be the intensity of outcoming light when analyer is rotated through 60^(@) .

Two polaroids are kept crossed to each other. Now one of them is rotated through an angle of 45^(@) . The percentage of incident light now transmitted through the system is

A ray of light is incident on a prism ABC of mu = sqrt(3) as shown in Fig. Find the angle of incidence for which the deviation of light by the prism ABC is minimum. By what angle should the second prism be rotated so that final ray suffers net minimum deviation ?

The unpolarised light is incident on polarisers placed above the other, so what is the angle between these two polarisers so that the than the intensity of the transmitted light is (1)/(3) than the intensity of incident light?

A horizontal ray of light passes through a prism of index 1.50 and apex angle 4^(@) and then strikes a vertical mirror , as shown in the figure. Through what angle must the mirror be rotated if after reflection the ray is to be horizontal?

Two lines passing through the point (2,3) intersects each other at an angle of 60°. If slope of one line is 2, find equation of the other line.

A conducting rod of mass 1 kg and length 1 m is suspended by two strings, so as to remain horizontal. If 2T horizontal magnetic field is applied perpendicular to the length of the rod then what amount of current should be passed through this rod to remove tension in two strings ? (Take g = 10ms^(-2) )

In an optics experiment, with the position of the object fixed, a student varies the position of a convex lens and for each position, the screen is adjusted to get a clear image of the object. A graph between the object distance u and the image distance v, from the lens, is plitted using the same scale for the two axes. A straight line passing through the origin and making an angle of 45^circ with x-axis meets the experimental curve at P. The coordinates of P will be.

Two blocks of mass m_(1)=10kg and m_(2)=5kg connected to each other by a massless inextensible string of length 0.3m are placed along a diameter of the turntable. The coefficient of friction between the table and m_(1) is 0.5 while there is no friction between m_(2) and the table. the table is rotating with an angular velocity of 10rad//s . about a vertical axis passing through its center O . the masses are placed along the diameter of the table on either side of the center O such that the mass m_(1) is at a distance of 0.124m from O . the masses are observed to be at a rest with respect to an observed on the tuntable (g=9.8m//s^(2)) . (a) Calculate the friction on m_(1) (b) What should be the minimum angular speed of the turntable so that the masses will slip from this position? (c ) How should the masses be placed with the string remaining taut so that there is no friction on m_(1) .

KUMAR PRAKASHAN-WAVE OPTICS-SECTION-D (MULTIPLCE CHOICE QUESTIONS (MCQS)) (MCQS FROM DARPAN BASED ON TEXTBOOK)
  1. What is the angle between the plane of polarisation and the direction ...

    Text Solution

    |

  2. In Young's double slit experiment, the intensity at a point P on the s...

    Text Solution

    |

  3. In a two tourmalines experiment, the polariser and analyser are crosse...

    Text Solution

    |

  4. In a arrangement of Young experiment the central fringe of interferenc...

    Text Solution

    |

  5. Two beams of light of intensity I(1), and I(2)interfere to give an int...

    Text Solution

    |

  6. In Young's double slit experiment if the width of 4^(th) bright fringe...

    Text Solution

    |

  7. The diameter of the pupil of human eye is 2.5 mm. Assuming the wavelen...

    Text Solution

    |

  8. Unpolarised light falls first on polarizer Pan then on analyzer A. If ...

    Text Solution

    |

  9. A plane polarized light is incident normally on a tourmaline plate. It...

    Text Solution

    |

  10. Light of wavelength lambda is incident on slit of width d. The resulti...

    Text Solution

    |

  11. If the wavelength of light is 4000 A, then the number of waves in 1 mm...

    Text Solution

    |

  12. Velocity of electromagnetic wave having wavelength 5000 Å in medium of...

    Text Solution

    |

  13. A diffraction pattern is formed by blue light, if blue light is replac...

    Text Solution

    |

  14. In Fraunhoffer diffraction by a single slit, the width of the slit is ...

    Text Solution

    |

  15. In Young's double slit experiment if the distance between two slits is...

    Text Solution

    |

  16. If the wavelength of light used is 6000 Å. The angular resolution of t...

    Text Solution

    |

  17. Match the terms in column I with those in column II

    Text Solution

    |

  18. Which of the following is wrong for interference fringes?

    Text Solution

    |

  19. A ray of light travelling in impure water is incident on a glass plate...

    Text Solution

    |

  20. In a Young double slit experiment, the width of the source slit is inc...

    Text Solution

    |