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A bomb of mass 20 kg is placed on a table suddenly it bursts into twoparts. Part of mass 8 kg moves with avelocity of 15 m/s, the velocity ofsecond part in m/s will be |
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Answer» Initially before explosion, CONSIDERING the bomb is at rest it’s velicity is zero.i.e. u1=u2=0 m/sWhen the bomb explodes into two pieces then:Mass of one part (m1)= 3kgVelocity of that part (V1)= 16m/sMass of another part (m2)= 6kgVelocity of another part (v2)= ? (we require that to find its kinetic energy)By the conservation of linear momentum:m1 * u1 +m2 * u2 = m1 * v1 + m2 * v2m1 * v1 + m2 * v2 = 0 (because u1 = u2 = 0)m1 * v1 = -m2 * v2 ( negative sign shows that they have OPPOSITE DIRECTION)So taking magnitude only:m1 * v1 = m2 * v23 * 16 = 6 * v2v2 = 8 m/sNow, kinetic energy (KE2) = 1/2 (m2 *v2^2)=0.5 * 6 * 8^2= 3 * 64=192 joulesHence the KE of of 6kg mass is 192 joules |
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