A person cannot see the object distinctly, when placed at a distance less than 100cm. What is the power of the spectacles that he should use to see clearly the objects placed at 25 cm?
1 Crore+ students have signed up on EduRev. Have you? Download the App |
A far- sighted person has lost his spectacles. He can read a book at usual distance by looking through a pin hole because while looking through the pin hole:
A myopic person can see things clearly if they lie between 8 cm and 100 cm from his eye. The lens will enable him to see the moon distinctly if its focal length is:
The earth takes 24 h to rotate once about its axis. How much time does the sun take to shift by 1º when viewed from the earth?
A slide projector gives a magnification of 10. If a slide of dimensions 3 cm x 2 cm is projected on the screen, the area of the image on the screen is:
What happens to the magnifying power of microscope, when its length increases?
The magnifying power of a telescope is 9. When it is adjusted for parallel rays, the distance between the objective and eyepiece is found to be 20 cm. The focal lengths of lenses are:
The distance of distinct vision of a person is 50 cm. He wants to read a book placed at 25 cm. What should be the focal length of the spectacles?
105 videos|425 docs|114 tests
|
Test: Ray Optics & Optical Instruments - 2 Test | 30 ques |
31 Year NEET Previous Year Questions: Ray Optics & Optical Instruments - 2 Test | 30 ques |
HC Verma Solutions: Chapter 17 - Light Waves Doc | 9 pages |
HC Verma Solutions: Chapter 18 - Geometrical Optics Doc | 21 pages |
HC Verma Solutions: Chapter 19 - Optical Instruments Doc | 7 pages |
105 videos|425 docs|114 tests
|
Test: Ray Optics & Optical Instruments - 2 Test | 30 ques |
31 Year NEET Previous Year Questions: Ray Optics & Optical Instruments - 2 Test | 30 ques |
HC Verma Solutions: Chapter 17 - Light Waves Doc | 9 pages |
HC Verma Solutions: Chapter 18 - Geometrical Optics Doc | 21 pages |
HC Verma Solutions: Chapter 19 - Optical Instruments Doc | 7 pages |