Answer:
Explanation:
Let the velocity of rocket case and payload after the separation be v₁ and v₂ respectively. v₂ will be greater because payload has less mass so it will be fired with greater speed .
v₂ - v₁ = 910
Applying law of conservation of momentum
( 250 + 100 ) x 7700 = 250 v₁ + 100 v₂
2695000 = 250 v₁ + 100 v₂
2695000 = 250 v₁ + 100 ( 910 +v₁ )
v₁ = 7440 m /s
v₂ = 8350 m /s
Total kinetic energy before firing
= 1/2 ( 250 + 100 ) x 7700²
= 1.037575 x 10¹⁰ J
Total kinetic energy after firing
= 1/2 ( 250 x 7440² + 100 x 8350² )
= 1.0405325 x 10¹⁰ J
The kinetic energy has been increased due to addition of energy generated in firing or explosion which separated the parts or due to release of energy from compressed spring.
