Question

A bomb of mass 30 kg at rest explodes into two pieces of masses 18 kg and 12 kg. The velocity of 18 kg mass is 6 ms^-1. The KE of other mass is

• A. 324 J
• B. 486 J
• C. 256 J
• D. 524 J

Answer 1

Answer: (B)

486 J

Answer 2

m₁v₁ = m₂v₂ ∴ v₂= $\frac { 18 \times 6 } { 12 }$= 9 ms^-1

KE = $\frac { 1 } { 2 }$ × 12(9)² = 486 J