(b) breakup of the nucleus of a heavy atom into two nearly equal halves
       emitting two or three neutrons and releasing large amounts of nuclear
       energy in the process
   (c) the scattering of neutrons
   (d) formation of heavier nucleus
Ans: (b)
354. Nuclear fusion is a process in which
   (a) the atoms and molecules lose their identity
   (b) nucleus is split into fragments
   (c) the nuclear reaction between two light atomic nuclei results in the
       formation of a heavier nucleus with release of a large quantity of nuclear
       energy in the process
   (d) absorption of neutron by a nucleus
Ans: (c)
355. Cosmic rays contain
   (a) protons and electrons
   (b) alpha particles
   (c) gamma rays
   (d) All the above
Ans: (d)
356. Cosmic rays are
   (a) powerful X-rays falling on the earth from space
   (b) ultraviolet rays from the sun
   (c) gamma rays from radioactive minerals
   (d) very energetic radiation falling upon the earth from outer space consisting
       chiefly of charged particles
Ans: (d)
357. The neutron, one of the constituent particles of which the nuclei of atoms
   are composed was discovered by
   (a) Irene Curie
   (b) W Bothe and H Becker
   (c) James Chadwick
   (d) Jean Joliot
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