Question

If a bomb at rest explodes into two pieces, the pieces must travel in opposite directions. Explain why?

Answer 1

According to conserve of linear momentum,
When external force acts on system of bodies = 0. then, linear momentum of system will be conserve.
e.g., initial momentum = final momentum

Initially, body of mass M is in rest.so, initial momentum = 0
Let finally, body explodes into two parts of mass m1 and m2 , m1 moves with velocity v1 and m2 moves with velocity v1.
so, final momentum = m1v1 + m2v2

Now initial momentum = final momentum
0 = m1v1 + m2v2
m1v1 = -m2v2
Here, negative sign indicates that velocity of bodies are in just opposite directions .
That's why If a bomb at rest explodes into two pieces, the pieces must travel in opposite directions

Answer 2

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