Home
Class 12
PHYSICS
Will the focal length of a lens for red ...

Will the focal length of a lens for red light be more, same or less than that for blue light ?

Text Solution

Verified by Experts

From lens maker.s formula
`(1)/(f)=(mu-1)((1)/(R_(1))-(1)/(R_(2)))`
We know that
`lambda_("blue")ltlambda_("red"))`
`therefore" "mu_("blue")gt mu_("red")`
`rArr" "f_("blue") lt f_("red")`
The focal length for the red light will be more t han for the blue light.
Promotional Banner

Topper's Solved these Questions

  • RAY OPTICS AND OPTICAL INSTRUMENTS

    MODERN PUBLICATION|Exercise Higher Order Thinking Skills & Advanced Level (QUESTIONS WITH ANSWERS)|20 Videos

  • RAY OPTICS AND OPTICAL INSTRUMENTS

    MODERN PUBLICATION|Exercise Revision Exercises (Very Short Answer Questions)|82 Videos

  • RAY OPTICS AND OPTICAL INSTRUMENTS

    MODERN PUBLICATION|Exercise NCERT (EXemplar Problems Obejective Questions) (Multiple Choice Questions (Type-II)|6 Videos

  • NUCLEI

    MODERN PUBLICATION|Exercise CHAPTER PRACTICE TEST FOR BOARD EXAMINATION|15 Videos

  • SEMICONDUCTOR ELECTRONICS METERIALS DEVICES AND SIMPLE CIRCUITS

    MODERN PUBLICATION|Exercise CHAPTER PRACTICE TEST FOR BOARD EXAMINATION|12 Videos

Similar Questions

Explore conceptually related problems

Wavelength of orange light is greater than that of blue light.

If the focal length of a double convex lens for red light is f_(R) its focal length for the violet light is

The wavelength of orange light is greater than that of blue light . True/False

Assertion : The focal length of the lens does not change when red light is replaced by blue light. Reason : The focal length of lens does not depends on colour of light used.

Assertion : The focal length of lens does not change when red light is replaced by blue light. Reason : The focal length of lens does not depends on colour of light used.

If f(V) and f_(R) are the focal lengths of a concex lens for violet and red light respectively and F_(V) and F_(R) are the focal lengths of concave lens for violet and red light respectively, then we have