Radar is used to
Rainbow formation is due to
The impression of an image persists on the retina for about _________ of a second.
Which of the following device is best suited for measuring the temperature inside metallurgical furnaces?
Device which uses sound waves for detection and ranging is called
Electric Motor converts ................ energy to mechanical energy.
A galvanometer can be converted into a voltmeter by connecting with it a
The atomic bomb is based on the principle of
What is the S.I. unit of temperature?
On the Moon, an astronaut cannot drink lemonade with the help of straw because