Ans: (a)
194. The element on which the first artificial radioactive features were
   experimented:
   (a) carbon
   (b) nitrogen
   (c) aluminium
   (d) None of these
Ans: (b)
195. The end element of every natural radioactive element is:
   (a) carbon
   (b) silicon
   (c) bismuth
   (d) sulphur
Ans: (a)
196. On which of the following specific resistance of a conducting wire
   depends? [NDA 2010]
   (a) length of the wire, cross-sectional area of the wire and on the matter of
       the wire
   (b) length of the wire, cross-sectional area of the wire but not on the matter
       of the wire
   (c) only on the matter of the wire but not on the length of the wire and cross-
       sectional area of the wire
   (d) only on the length of the wire and neither on the cross-sectional area of
       the wire nor on the matter of the wire
Ans: (b)
197. The disintegration process of a heavy nucleus into two lighter nuclei is
   called: [RRB 2003]
   (a) Nuclear fusion
   (b) Nuclear fission
   (c) Radioactive disintegration
   (d) Mass loss
Ans: (b)
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