<P> A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions , either fission ( fission bomb ) or from a combination of fission and fusion reactions ( thermonuclear bomb ) . Both bomb types release large quantities of energy from relatively small amounts of matter . The first test of a fission ( `` atomic '' ) bomb released an amount of energy approximately equal to 20,000 tons of TNT ( 84 TJ ) . The first thermonuclear ( `` hydrogen '' ) bomb test released energy approximately equal to 10 million tons of TNT ( 42 PJ ) . A thermonuclear weapon weighing little more than 2,400 pounds ( 1,100 kg ) can release energy equal to more than 1.2 million tons of TNT ( 5.0 PJ ) . A nuclear device no larger than traditional bombs can devastate an entire city by blast , fire , and radiation . Since they are weapons of mass destruction , the proliferation of nuclear weapons is a focus of international relations policy . </P>
<P> A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions , either fission ( fission bomb ) or from a combination of fission and fusion reactions ( thermonuclear bomb ) . Both bomb types release large quantities of energy from relatively small amounts of matter . The first test of a fission ( `` atomic '' ) bomb released an amount of energy approximately equal to 20,000 tons of TNT ( 84 TJ ) . The first thermonuclear ( `` hydrogen '' ) bomb test released energy approximately equal to 10 million tons of TNT ( 42 PJ ) . A thermonuclear weapon weighing little more than 2,400 pounds ( 1,100 kg ) can release energy equal to more than 1.2 million tons of TNT ( 5.0 PJ ) . A nuclear device no larger than traditional bombs can devastate an entire city by blast , fire , and radiation . Since they are weapons of mass destruction , the proliferation of nuclear weapons is a focus of international relations policy . </P>
where does a nuclear bomb get its energy from
where does a nuclear bomb get its energy from
nuclear reactions , either fission ( fission bomb ) or from a combination of fission and fusion reactions ( thermonuclear bomb )
nuclear reactions , either fission ( fission bomb ) or from a combination of fission and fusion reactions ( thermonuclear bomb )