Q.21)-Matter waves are
- de Broglie waves
- Electromagnatic waves
- Transverse waves
- Longitudinal waves
Q.22)-Which electromagnetic radiation is used for setellite communication?
- Ultraviolet
- Infrared
- Microwave
- Millimeter wave
Q.23)-The radiation initially produced in fluorescent tube is
- Infrared
- Ultraviolet
- Microwaves
- X-Rays
Q.24)-Waves that are required for long distance wireless communication are
- Infrared Rays
- Ultraviolet Rays
- Radio waves
- Microwaves
Q.25)-Ultra violet raditations of the sun do not reach the earth because, earth's atmosphere is surrounded by
- Carbon dioxide
- Ammonia
- Chlorine
- Ozone
Q.26)-Gamma rays can cause
- Gene mutation
- Sneezing
- Iodine
- Sodium chloride
Q.27)-Ultraviolet radiations has more energy as compare to-
- Infrared Radiation
- Gamma Radiation
- X-Rays
- Space Rays
Q.28)-Ultraviolet rays can be used in water treatment as
- Precipitator
- Hydrolyser
- Disinfectant
- Flocculator
Q.29)-The device used for measuring the wavelength of X-rays is:
- Cyclotron
- Bragg's Spectrometer
- Mass spectrometer
- GM counter
Q.30)-Radar is used to-
- To locate submerged submarines
- Receive signal from radio receivers
- Detect and locate distant objects
- Locate geostationary satellites