A box of mass m = 6 kg slides with speed v = 4 m/s across a frictionless floor. It explodes into two pieces: one piece, with mass m1 = 2 kg move in the same direction with speed v1 = 8 m/s. Find the velocity of the second piece.
Correct answer: A. 2 m/s
- A. 2 m/s
- B. 4 m/s
- C. 8 m/s
- D. 9 m/s
- E. 11 m/s
Explanation
Before explosion m1 = 6 kg , u1 = 4m/s After the explosion, it explodes into two pieces, such that m1 = 2kg, v1 = 8m/s, m2 = 4 kg, v2 =? In case of an explosion, momentum will remain conserved. According to the Law of Conservation of Momentum: Momentum before explosion =Momentum after the explosion m1u1 = m1v1 + m2v2 (6)(4) = (2)(8)+(4)(v2) 24 = 16 + 4v2 8 = 4v2 v2 = 2 m/s
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