Q. Assertion : Thermonuclear fusion reactions may become the source of unlimited power for the mankind.
Reason : A single fusion event involving isotopes of hydrogen produces more energy than energy from nuclear fission of

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Solution:

When fusion is achieved by raising the temperature of the system so that particles have enough kinetic energy to overcome the coulomb repulsive behaviour, it is called thermonuclear fusion. It is clean source of energy but energy released in one fusion is much less than a single uranium fission.