Question

An explosion breaks an object into two pieces, one of which has 1.5 times the mass of the other. If 7500 J were released in the explosion, how much kinetic energy dideach piece acquire?

heavier piece


lighter piece

Answer 1

According to conservation of momentum0 = m1 V1 + m2 V2Given that m2 = 1.5 m1 , soV1 = -1.5 V2the kinetic energy of each piece isK2 = (1/2) m2 V2^2K1 = (1/2) m1 V1^2substituting the value of V1 in the above equationK1 = (1/2)( m2 / 1.5 )( -1.5 V2)^2 = 1.5 (1/2)m2 V2^2 = 1.5 K2Given thatK1 + k2 = 7500 J1.5 K2 + K2 = 7500K2 = 7500 / 2.5= 3000Jthis is the KE of heavier massK1 = 7500 - 3000 = 4500 Jthis is the KE of lighter mass