Advertisements
Advertisements
प्रश्न
Define its magnifying power and write the expression for it?
Advertisements
उत्तर
Magnifying Power: The magnifying power m is the ratio of the angle α subtended at the eye by the final image to the angle β which the object subtends at the lens or the eye.
`m≈ β/α h/f_e . f_o/h = f_o/f_e`
APPEARS IN
संबंधित प्रश्न
A small telescope has an objective lens of focal length 144 cm and an eyepiece of focal length 6.0 cm. What is the magnifying power of the telescope? What is the separation between the objective and the eyepiece?
- For the telescope is in normal adjustment (i.e., when the final image is at infinity)? what is the separation between the objective lens and the eyepiece?
- If this telescope is used to view a 100 m tall tower 3 km away, what is the height of the image of the tower formed by the objective lens?
- What is the height of the final image of the tower if it is formed at 25 cm?
Draw a labelled ray diagram of an image formed by a refracting telescope with the final image formed at infinity. Derive an expression for its magnifying power with the final image at infinity
Draw a ray diagram showing the image formation of a distant object by a refracting telescope ?
How is the working of a telescope different from that of a microscope?
The eyepiece of an astronomical telescope has a focal length of 10 cm. The telescope is focussed for normal vision of distant objects when the tube length is 1.0. m. Find the focal length of the objective and the magnifying power of the telescope.
(i) What is meant by resolving power of a telescope?
(ii) State any one method of increasing the resolving power of an astronomical telescope.
Draw a labelled ray diagram showing the formation of an image by a refracting telescope when the final image lies at infinity.
Draw a ray diagram of astronomical telescope for the final image formed at infinity.
A small telescope has an objective of focal length 140 cm and an eye piece of focal length 5.0 cm. The magnifying power of telescope for viewing a distant object?
