The angular magnification of a telescope is `300` What should be the diameter of the objective, if our eyes at the eye ring, are just able to collect all the light refracted from the objective. Take diameter of pupil of eye `= 3mm`.

Is angular magnification of a telescope equal to ratio of diameters of objective and eye lens ?

What is the distance between objective and eye lens of telescope in normal adjustment ?

Angular magnification of telescope if focal length of objective and eye lenses are 10 cm and 10 mm respectively and tube length is 11cm:

Angular magnification of telescope if focal length of objective and eye lenses are 10 cm and 10 mm respectively and tube length is 11cm:

At what magnification T of a telescope with a diameter of the objective D = 6.0 cm is the illuminance of the image of an object on the retina not less than without the telescope ? The pupil diameter is assumed do be equal to d_(0) = 3.0 mm . The losses of light in the telescope are negligible.