<span>The best response would be that theories are not opinions. While laws and theories are similar, laws tend to be a collection of theories about the same phenomenon. Laws can be expressed as math formulae, but more often they're in the form of "if-then" statements. Laws and theories both have to be rigorously tested before they reach these classiffications.</span>
Answer:
the product of mass and velocity
....in my syllabus
According to the condensation theory, the most important factor for the formation of our planets was "the interstellar dust attracting heat away from the protosun".
Condensation is the procedure by which water particles noticeable all around bunch together and shape fluid water. This is regularly observed outwardly of cold glasses. This idea additionally identifies with the solar system.
The condensation theory of the solar system expresses that our solar system, and perhaps all other galaxies, were shaped from a cloud of residue and gas that consolidated into strong issue. Space experts trust that the littlest grains of residue in our cloud applied a draw on the gas about it, 'consolidating' into bigger and bigger bits of issue, similarly as a snowball moving downhill will become bigger and bigger. In the long run, the gravitational draw of these residue atoms was sufficiently solid that they started to pull in each other, developing into greater and greater clusters that had more grounded gravitational pulls. In the long run, these bunches of residue and gas from the cloud frame a star, and potentially planets, space rocks, and comets turning about the star.
Before getting an answer for it first we have to understand nuclear fusion.
Nuclear fusion is a thermo-nuclear reaction in which two light unstable nuclei will form a heavy stable nuclei. In this process there will be some mass defect which will be converted into energy as per Einstein's mass energy equivalence theorem.
The theorem is stated as 
where c is the velocity of light and m is the mass converted into energy.
One take an example of fusion in sun where 4 hydrogen atoms combine to form a helium nucleus which are explained below-
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Here 
is the positron.
In this process very high temperature is needed which is approximately equal to the temperature of the sun i.e 
Such temperature is very difficult to initiate the reaction on the earth surface. It should be carried out in an sustainable way also .Otherwise It will cause nuclear hazards.
