The not nuclear fusion reaction inside the Sun can be writte

The not nuclear fusion reaction inside the Sun can be written as 4^1 H rightarrow^4 He. + E. The rest energy of each hydrogen atom is 938.78MeV, and the rest, energy of the helium-4 atom is 3728.4MeV. (a) Calculate the percentage of the starting mass that is transformed to other forms of energy. (b) If that energy were converted to the kinetic energy of a 1kg cannon ball, how fast would the cannon ball be traveling in meters per second?

Solution

a)

The relation between mass and energy is given by-

E=mc²

Now change in rest energy = 4*(Rest energy of H) - (Rest energy of He)

=(4*938.78-3728.4) MeV

=26.72MeV

Thus % mass converted to other forms of energy= (26.72MeV/c²)/(3755.12MeV/c²)*100

=0.71%

b)

26.72MeV=26.72*10⁶*1.6*10^-19J=4.28*10^-12J

K.E energy of 1Kg cannon ball=0.5*1*v²

Thus v= sqrt(2*4.28*10^-12)=2.9*10^-6m/s