Optical Instruments

The function of collimeter in spectrometer is________________? A. to produce parallel beams of light B. to filter the light rays C. to make them D. no function

Errors in the transmission of power through optic fiber can be minimized by using a______________? A. Multimode index fiberB. Graded index fiber C. Single mode step index fiber D. Copper wire

Magnification of the astronomical telescope is_____________? A. fo+feB. fo/fe C. fe/fo D. (1+fo/fe)L/fo

In optic fiber transmission system _____________ are used regenerate the dim light signal? A. DiodesB. Repeaters C. Laser D. Transformer

The value of critical angle for glass is_______________? A. 42° B. 47° C. 52° D. 50°

A point where the incident parallel rays of light converge or appear to diverge after passing through a lens is called______________? A. center of curvatureB. focus C. optical center D. aperture…

Dioptre power of an concave lens of 10 cm focal length is_______________? A. 10 dioptreB. 10 dioptre C. 1 / 10 dioptre D. 1 / 10 dioptre

The minimum distance between an object and its real image in a convex lens is_____________? A. 2 f B. 2.5 f C. 3fD. 4f

A convex lens gives a virtual image only when the objects lies_________________? A. between principal focus and center of curvature B. beyond 2 f C. at the principal focusD. between principal focus and optical center…

Image of an object 5 mm high is only 1 cm high. Magnification produced by lens is__________________? A. 0.5 B. 0.2 C. 1D. 2