41) The atmosphere exerts enormous pressure on us. But we did not feel it because:
(A) We are used to it
(B) Our bones are very strong and can withstand this pressure
(C) The surface area of our head is very small
(D) Our blood exerts a pressure slightly more than that of the atmosphere
42) Lightning is formed when:
(A) Similar charges of electricity rush towards each other and then get repelled
(B) Clouds strike against impurities in air and the friction burns up these impurities
(C) Strong opposite charges in different clouds breakdown the resistance offered by the intervening air
(D) Water vapor produces electricity in the clouds
43) A semiconductor is also used in
(A) Capacitor
(B) Transformer
(C) Electronic motor
(D) Rectifier
44) The wave which does not require any medium is
(A) Sound waves
(B) Air waves
(C) Electromagnetic waves
(D) Water waves
45) Radio waves are
(A) Sound waves
(B) Electromagnetic waves
(C) Water waves
(D) Heat waves
46) AC voltage is
(A) Chemical quantity
(B) Digital quantity
(C) Analog quantity
(D) Mathematical quantity
47) In Binary system, 361 is written as
(A) 10101101
(B) 1001101
(C) 10110111
(D) 101101001
48) The device which converts analog signal to digital signal is called
(A) Transformer
(B) CPU
(C) Modem
(D) Photodiode
49) For making laser usually we use
(A) Uranium
(B) Ruby
(C) Magnesium
(D) Iron
50) Argon laser is used for operating the
(A) Eye cancer
(B) Glaucoma
(C) Kidney stone
(D) Bone disease