The quantity of matter in a body regardless of its volume or of any forces acting on it.
Answer:
0.074m/s
Explanation:
We need the formula for conservation of momentum in a collision, this equation is given by,

Where,
= mass of ball
= mass of the person
= Velocity of ball before collision
= Velocity of the person before collision
= velocity of ball afer collision
= velocity of the person after collision
We know that after the collision, as the person as the ball have both the same velocity, then,


Re-arrenge to find
,

Our values are,
= 0.425kg
= 12m/s
= 68.5kg
= 0m/s
Substituting,


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<em>The speed of the person would be 0.074m/s after the collision between him/her and the ball</em>
D, as the others will result in the likelihood of the particles colliding decreasing
Hope it helps))
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