What impulse was delivered to the ball by the player?

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The discussion revolves around calculating the impulse delivered to a soccer ball by a player. The ball, initially moving at 18 m/s to the north, is struck by the player, reversing its direction to 24 m/s south. The impulse is determined by the change in momentum, calculated as the mass of the ball multiplied by the change in velocity. The correct calculation yields an impulse of -19.74 kg*m/s, indicating the direction of the force applied by the player. The final answer reflects the negative sign due to the change in direction of the ball.
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Homework Statement



A 0.47 kg soccer ball approaches a player horizontally with a velocity of 18 m/s to the north. The player strikes the ball and causes it to move in the opposite direction with a velocity of 24 m/s.

What impulse was delivered to the ball by the player? Answer in kg*m/s


Homework Equations



impulse = change in momentum
momentum = mv


The Attempt at a Solution



0.47((24-(-18)) = 19.74 kg*m/s

or would it be

0.47(24-18) = 2.82 kg*m/s

i'm lost
 
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The change in momentum will be

mv_1-mv_2 = m(v_1-v_2)

Now keep in mind these are vectors. So one will be a negative number...

.47 kg (18 - (-24) \frac{m}{s})
 
Bill Foster said:
The change in momentum will be

mv_1-mv_2 = m(v_1-v_2)

Now keep in mind these are vectors. So one will be a negative number...

.47 kg (18 - (-24) \frac{m}{s})
oops i meant - 2.82, it says it wrong
 
Nevermind I got it

0.47(-24-18) = -19.74 that's the answer
 
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