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Grade 12General Physics

A 30 kg shell moving in free space explodes into three fragments of equal masses. After explosion, the fragments move apart under influence of their mutual forces of interactions. At some instant of time after the explosion, velocities of the fragments relative to an inertial frame are (3î + 2ĵ)m/s, –2î m/s and (5î – 5ĵ)m/s.
If whole of the energy released in the explosion is converted into kinetic energy of the three fragments, how much energy has been released in the explosion?
(1) 260 J
(2) 290 J
(3) 335 J
(4) 410 J

Profile image of amogh joshi
11 Years agoGrade 12
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1 Answer

Profile image of Abhishek
11 Years ago
it would be 335J.You just need sum up all the kinetic energies of the indiidual fragments by calculating their elovcities using vector methods. for ex for the first one we have v1=sqrt(3^2+2^2).