The focal length of the objective lens of a telescope is 30 cm and that of its eye lens is 3 cm. It is focussed on a scale 2 metres distant from it. The distance of the objective lens from the eye lens to see with relaxed eye is :-

The focal length of objective lens of a telescope is 30 cm and that of its eye lens is 3 cm. It is focussed on a scale 2 metres distant from it. The distance of objective lens from eye lens to see with relaxed eye is

The focal length of the objective lens of a telescope is 50 cm If the magnification of the telescope is 25, then the focal length of the eye-piece is

Find the power of the eye lens of the normal eye when it is focussed at its near point. Assume the distance of the retina from the eye lens to be 2.5 cm.

The focal length of objective and eye lens of a microscope are 4 cm and 8 cm respectively. If the least distance of distinct vision is 24 cm and object distance is 4.5 cm from the objective lens, then the magnifying power of the microscope will be

The focal length of objective and eye lens of a microscope are 4 cm and 8 cm respectively. If the least distance of distinct vision is 24 cm and object distance is 4.5 cm from the objective lens, then the magnifying power of the microscope will be