Question

Momentum in an Explosion

A giant "egg" explodes as part of a fireworks display. The egg is at rest before the explosion, and after the explosion, it breaks into two pieces, with piece B moving in the positive x direction. The masses of both pieces are indicated in (Figure 1) , shown traveling in opposite directions.

A = 10kg

b = 30 kg

What is the magnitude of the momentum |p⃗A,i | of piece A before the explosion?

Express your answer numerically in kilogram meters per second.

During the explosion, is the magnitude of the force of piece A on piece B greater than, less than, or equal to the magnitude of the force of piece B on piece A?

greater than

less than

equal to

The component of the momentum of piece B, pBx,f , is measured to be +500 kg⋅m/s after the explosion. Find the component of the momentum pAx,f of piece A after the explosion.

Enter your answer numerically in kilogram meters per second.

Answer 1

*
Since the egg is at rest, the momentum P_A,i=m_AV_A,i is zero.

*
The momentum is conserved before and after the explosion
P_A,i + P_B,i = P_A,f +P_B,f
0 = P_A,f + P_B,f
P_A,f = -P_B,f
Then P_A,f = -500 kg.m/s

*
Since

and both pieces end with the same magnitude of momentum afterthe explosion, the forces between the pieces must be the same inmagnitude (but opposite directions).

F= 노