In a photometer two sources of light when placed at 30 and 50 cm respectively produce shadow of equal intervals. Their candles are in the ratio of
READ MORE +Light MCQs
Two thin lenses, one of focal length +60 cm and the other of focal length -20 cm are kept in contact. Their combined focal length is
READ MORE +
A blue object on a white background when seen through a blue filter will appear
READ MORE +
When light travels from one medium to other whose refractive index is different, then which of the given will change?
READ MORE +
For which of the given is luminous efficiency maximum ?
READ MORE +
The focal length of a concave mirror is f and the distance of the object to the principal focus is p . Then the ratio of the size of the image to the size of the object is
READ MORE +
Monochromatic light of frequency 5 x 10⁴ Hz travelling in vacuum enters a medium of refractive index 1.5. Its wavelength in the medium is :
READ MORE +
At what distance from a screen will a 27 Cd lamp provide the same illumination as a 75 Cd lamp 15 m from the screen?
READ MORE +
In an astronomical telescope the focal length of objective lens is 100 cm and that of eyepiece is 2 cm. The magnifying power of the telescope for the normal eye is
READ MORE +
Large aperture objects are used in telescopes because they
READ MORE +
Light with wavelength of 6000 A0 units has a frequency
READ MORE +
A ray reflected successively from two plane mirrors inclined at a certain angle undergoes a deviation of 3000. Then the number of images observable is :
READ MORE +- « Previous Page
- 1
- 2
- 3
- 4
- 5
- 6
- …
- 15
- Next Page »