198. The formation of a heavy nucleus by the combination of two lighter
   nuclei is:
   (a) nuclear fission
   (b) nuclear fusion
   (c) photoelectric effect
   (d) chemical reaction
Ans: (b)
199. Atom bomb is based upon the principle of: [BPSC (Pre) 1994]
   (a) nuclear fusion
   (b) nuclear fission
   (c) both of them
   (d) None of these
Ans: (b)
200. Hydrogen bomb is based upon the principle of:
   (a) nuclear fusion
   (b) nuclear fission
   (c) both of them
   (d) None of these
Ans: (a)
201. Which types of waves are utilized in the night visionary equipment? [IAS
   (Pre) 2009]
   (a) Radio wave
   (b) Micro wave
   (c) Infrared wave
   (d) None of these
Ans: (c)
202. When X-rays are produced, then [NDA 2010]
   (a) heat is produced on the target
   (b) heat is absorbed by the target
   (c) temperature of the target is being constant
   (d) a luminous light is to be seen on the target
Ans: (c)
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