In a terrestrial telescope, the focal length of objective is `90cm` and of eye lens is `6 cm`. If the final image is at `30cm`, then the magnification will be

In a terrestrial telescope, the focal length of objective is 90cm , of inverting lens is 5 cm and of eye lens is 6 cm . If the final image is at 30cm , then the magnification will be the final image is at 30cm, then the magnification will be

For a telescrope, focal length of objective lens is 15 cm and focal length of eye piece is 10 mm. if tube length is 16 cm, then find the magnification.

In an astronomical telescope, the focal length of the objective lens is 100 cm and of eye-piece is 2 cm . The magnifying power of the telescope for the normal eye is

In an astronomical telescope, focal length of eye piece is 5 cm and focal length of objective is 75 cm . The final image is formed at the least distance of distinct vision (=25 cm) from the eye. What is the magnifying power of the telescope ?

In an astronomical telescope, the focal length of objective lens and eye-piece are 150 cm and 6 cm respectively. In case when final image is formed at least distance of distinct vision. the magnifying power is

An astronomical telescope has focal lengths 100cm & 10cm of objective and eyepiece lens respectively. When final image is formed at least distance of distinct vision, magnification power of telescope will be:

The focal length of a convex lens is 20 cm . If an object of height 2 cm is placed at 30 cm from the lens , find the magnification produced by the lens .

The focal length of a convex lens is 30cm and the size of the real image is (1)/(4)th of the object. Then the object distance is