1.
In optical instruments, the lenses are used to form image by the phenomenon of-
2.
Heavy water is used as a moderator a nuclear reactor. The function of the moderator is-
3.
Which one among the following colours has the highest wavelength?
4.
Which of the following electromagnetic waves has the longest wavelenght?
5.
When two semiconductors of p- and n-type are brought in contact, they form p-n junction which acts like a/an-
6.
The photoelectric effect is described as the ejection of electrons from the surface of a metal when-
7.
Centigrade and Fahrenheit temperatures are the same at-
8.
If the pressure in a closed vessel is reduced by drawing out some gas, the mean free path of the gas molecules will-
9.
The method of communication in which transmission can take place in both directions, but happens only in one direction at a time, is called-
10.
Permanent magnet can be made from-
11.
Water drops do not stick to the oily surface due to-
12.
When water is heated from 0°C to 10°C its volume-
13.
When the milk is churned vigorously the cream from it, is separated out due to-
14.
Light year is the unit of-
15.
A fuse wire is characterised by-
16.
When the same note is played on a sitar and a flute, the sound produced can be distinguished from each other because of the difference in-
17.
The velocity of sound in moist air is more than in dry air because the moist air has-
18.
If potential difference and current flowing through a wire is increased twice each then electric power-
19.
The phenomenon which cause mirage is-
20.
Decibel is the unit of-
21.
A defect of vision in which the point in one plane of an object appear in focus while those in another plane are out of focus is called-
22.
Perspiration cools the body because-
23.
A passenger in a moving train tosses a coin upward which falls behind him. It implies that the motion of the train is-
24.
Different objects at different distances are seen by the eye. The parameter that remains constant is-
25.
Creation of something from nothing is against the law of-
