Ozone layer prevents ______________ radiation from entering the atmosphere
(A) Infra-red
(B) Ultraviolet
(C) X-rays
(D) Gamma rays
(D) None of these
Which one of the following is a non_metallic mineral
(A) Manganese
(B) Magnesium
(C) Gypsum
(D) Bauxite
(D) None of these
A moderator is used in nuclear reactor in order to
(A) Accelerate the neutrons
(B) Slow down the speed of the neutrons
(C) Increase the number of elections
(D) Decrease the number of electrons
(D) None of these
Which of the following atmospheric layers help in radio communication
(A) Exosphere
(B) Ionosphere
(C) Troposphere
(D) Stratosphere
(D) Ozone layer
Monsoon is caused by____________________
(A) Seasonal reversal of winds
(B) Revolution of earth
(C) Movement of clouds
(D) Rise in temperature
(D) Rain forests
Fuel used in a Fast Breeder Reactor is _____________
(A) Uranium Oxide
(B) Uranium Plutonium carbide
(C) Uranium Plutonium Oxide
(D) Uranium thorium Oxide
(D) None of these
Kilowatt_hour is a unit of____________
(A) Power
(B) Electric Current
(C) Energy
(D) Time
(D) None of these
The term 'Blue Shift' is used to indicate
(A) Doppler effect in which an object appears bluer when it is moving towards the observer or observer is moving towards the object.
(B) Turning a star from white to blue
(C) In future sun would become blue
(D) Black hole was blue at its start
(D) None of these
The half life of a radioactive element is 8_days How long it take to reduce it from 10 mg to 5 mg
(A) 4 days
(B) 12 days
(C) 16 days
(D) 8 days
(D) None of these