Home
Class 12
PHYSICS
What is power of a lens?...

What is power of a lens?

Text Solution

Verified by Experts

The power of a lens P is defined as the reciprocal of its focal length. P=`(1)/(f)`The unit of power is diopter D.
Promotional Banner

Topper's Solved these Questions

  • SAMPLE PAPER-05 ( SOLVED )

    FULL MARKS|Exercise PART-III|9 Videos

  • SAMPLE PAPER-05 ( SOLVED )

    FULL MARKS|Exercise PART - IV|10 Videos

  • SAMPLE PAPER-05 ( SOLVED )

    FULL MARKS|Exercise PART - IV|10 Videos

  • SAMPLE PAPER 9

    FULL MARKS|Exercise PART-IV|10 Videos

  • SAMPLE PAPER-07 (SOLVED )

    FULL MARKS|Exercise (PART - IV)(Answer all the questions.)|10 Videos

Similar Questions

Explore conceptually related problems

1D is the power of a lens whole focal length is ________.

A normal eye has retina 2 cm behind the eye-lens. What is the power of the eye-lens when the eye is (a) fully relaxed, (b) most strained?

A person has near point at 100 cm. What power of lens is needed to read at 20 cm if he/she uses (a) contact lens, (b) spectacles having glasses 2.0 cm separated from the eyes?

a. The far point of a myopic person is 80cm in front of the eye. What is the power of the lens required to enable him to see very distant object clearly ? b. In what way does the corrective lens help the above person ? Does the lens magnify very distant objects? Explain carefully. c. The above person profers to remove his spectacles while reading a book Explain why.

a. The near point of a hypermetropic person is 75 cm from the eye. What is the power of the lens required to enable the person to read clearly a book held at 25 cm from the eye? b . In what way does the corrective lens help the above person? Does the lens magnify objects held near the eye ? c. The above person prefers to remove the spectacles with looking at the sky. Explain why .

Draw a plot showing the variation of power of a lens with the wavelength of the incident light.