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## Homework Statement

Okay, we have a lab about elastic and inelastic collision, and we have to do it in an air table/spark table that generates dots (can be like ticker tapes). We have to determine Momentum (P and P') and Kinetic Energy (Ek and Ek')

Please view my attachment.

(' = after collision)

our data:

distance

d1 = 0.21 m

d1' = 0.34 m

d2 = 0.21 m

d2' = 0.32 m

time

t1=0.3s

t1'=0.5s

t2=0.3s

t2'=1.0s

I get that everything is straightforward, but since its a lab and I have no partner, I wanted to make sure my equations and calculations are right (there's no handout to refer, or textbook examples)

I already solved the initial velocity, for the velocity after, do I use equation

**1**or

**3**?

For solving P, we use

**2**right? Or no? and we find P' using

**3**?

We won't be using the degrees, right?

And we don't need

**4**right?

Lastly, for Ek, we use

**5**to get the Ek? but what do we use/do to get Ek'? Do we use

**5**or

**6**

## Homework Equations

**1**Velocity: V=d/t

**2**Momentum: P=mv

**3**Momentum(?)/Collision(?): m1V1 + m2V2 = m1V1' + m2V2'

**4**Work: W=F(cosθ)d

**5**Kinetic Energy: Ek=1/2mv

^{2}

**6**Ek=Ek'

## The Attempt at a Solution

I already solved the initial velocity:

V1 = 0.21/0.3

= 0.7 m/s

V2 = 0.21/0.3

= 0.7 m/s

for the velocity after, I tried doing both

**1**and

**3**. But I got two different answers (When solving for V1' or V2', I used the V1' or V2' in the equation). So do I stick to

**1**?

V = d/t

V1'= 0.34/0.5

= 0.7 m/s

V2' = 0.32/1

= 0.32 m/s

The rest of the question, I am stuck. I want to continue solving but then, I realize I might screw up on parts and get zero on my lab. See, I'm getting confused on which equations to use.

I am just looking for guidelines, not answers.

I hope you guys can help me. Thanks a lot:)

#### Attachments

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