(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Before a collision, a 25-kg object is moving at +12m/s. Find the impulse that acted on teh object if, after the collision, it moves at:

a. 8.0m/s

b.-8.0m/s

2. Relevant equations

(c)=changes in:

To find impulse, we would use the F=ma, so F=m*(c)v/(c)t

So, F(c)t = m(c)v

Therefore, F(c)t=p2-p1 (impulse-momentum theorem).

3. The attempt at a solution

Ok, so here's what I did. Let's solve A first.

GIVEN:

m=25kg

v1=12m/s

v2=8m/s

F=25*(8.0-12)/(c)t

F= -100/(c)t

So, we take the difference in time to the other side.

F(c)t=-100

Therefore, its impulse is -100. At first I got confused because I had left two variables, but I think that's the impulse because F(c)t=p2-p1, so:

p2-p1=-100

25(8)-(25)(12)=-100

-100=-100

Im assuming thats the impulse, so its -100 N*s.

So, lets do this for B, which is -8.

GIVEN:

m=25kg

v1=12m/s

v2=-8.0m/s

F=?

F(c)t=m(v2-v1)

Impulse=25(-8-12)

Impulse=25(-20)

Impulse=-500

Seems to make sense, because to make the object thats moving go on its opposite direction it must be really strong. And also, both answers are negative as it moves in the opposite direction.

I would appreciate if you could check over my work to see if it is correct.

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# Homework Help: Find the Impulse and Momentum

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