Short Answer Type(i) Write a balanced equation showing nuclear fission of Uranium 
(ii) In a nuclear reactor, what is the function of:
(1) Cadmium rods? (2) Graphite rods?
(i) A balanced equation showing nuclear fission of Uranium nucleus is
92U235 + 0n1 → 56Ba141 + 36Kr92 + 3(0n1) +200MeV.
(Uranium) (Barium Krypton)
(ii)
1. To maintain the steady rate of fission, the neutron absorbing material known as controller is used. The controller rods are made of cadmium.
2. A moderator is a suitable material to slow down neutrons produced in the fission. For this the moderator rods are graphite rods.
On an energy level diagram of hydrogen, show by a downward or an upward arrow, a transition which results in:
(i) Emission line of Balmer series.
(ii) Emission line of Lyman series.
(iii) Absorption line of Lyman series.
and Its binding energy in MeV.
Mass of a proton = 1.007276 u
Mass of a neutron = 1.008665 u
Mass of 
nucleus = 4.001506 u
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