Calculating Speed after Impulse of 6 Ns

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A 2kg object moving at 4 m/s experiences an impulse of 6 Ns, prompting a discussion on calculating its final speed. The initial momentum is calculated as 2(4), and the impulse represents the change in momentum. After some confusion, the correct equation is established as 2v - 2(4) = 6, leading to the final speed of 7 m/s. The participants clarify the direction of the impulse and confirm the calculations. The final speed after the impulse is accurately determined to be 7 m/s.
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Homework Statement


A 2kg object is moving to the right with a speed of 4 m/s when it experiences an impulse of 6 Ns .


Homework Equations



mv+mv=mv

The Attempt at a Solution


Since the impulse is just the change in momentum I put in 2(4)+2v=6 so wouldn't v be -1?
 
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hi kerbyjonsonjr! :wink:

(btw, which direction is the impulse?)
kerbyjonsonjr said:
Since the impulse is just the change in momentum …

yes that's correct :smile:
… I put in 2(4)+2v=6 so wouldn't v be -1?

what is 2(4)+2v=6 supposed to be? :confused: …

the impulse is the difference between the momentum after and before …

try again :smile:​
 
got it now! thanks for the help! I messed up. It should have been the final minus the initial. So it's 2v-2(4)=6 which gets me v= 7 m/s. Thanks for the help!
 

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