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## Main Question or Discussion Point

I had a physics lab for Hooke's Law and Simple (ha!) Harmonic Motion. I am not pleased with my grade, but my professor did not indicate what I did wrong and I am banging my head against the wall trying to figure it out (btw, it's not helpful). So if any of you all can take a gander at it and tell me hey! You did this wrong! That would be great. Thank you.

First Section: Spring Elongation

weight(grams)*9.18m/s^2 | Scale reading (mm)

m1g = 114.26 | y1 4.7

m2g = 124.26 | y2 = 5.2

m3g = 134.26 | y3 = 5.9

m4g = 144.26 | y4 = 6.3

m5g = 154.26 | y5 = 6.7

m6g = 164.26 | y6 = 7.3

m7g = 174.26 | y7 = 7.8

m8g = 184.26 | y8 = 8.2

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Okay, the first thing I did was convert the grams to kg and multiply by g (9.8m/s^2).

For these values I got:

mg1=1.12N, mg2=1.22N, mg3=1.3157N, mg4=1.414N, mg5=1.512N, mg6=1.61N, mg7=1.708N, mg8=1.806N

Then I converted mm to m....0047, .0052, .0059, .0063, etc.

It's asking for k and in parentheses next to it has slope of graph. [ie k(slope of graph)] So k=slope of graph. Slope equals rise/run, (delta y)/(delta x). So I choose two points 1 & 4.

(1.12N - 1.414N) / (.0047m - .0063m) = -0.294N / -.0016m = 183.75 N/m.

His answer is k = 20. Where did go wrong to get a value so far from the answer?

First Section: Spring Elongation

weight(grams)*9.18m/s^2 | Scale reading (mm)

m1g = 114.26 | y1 4.7

m2g = 124.26 | y2 = 5.2

m3g = 134.26 | y3 = 5.9

m4g = 144.26 | y4 = 6.3

m5g = 154.26 | y5 = 6.7

m6g = 164.26 | y6 = 7.3

m7g = 174.26 | y7 = 7.8

m8g = 184.26 | y8 = 8.2

---

Okay, the first thing I did was convert the grams to kg and multiply by g (9.8m/s^2).

For these values I got:

mg1=1.12N, mg2=1.22N, mg3=1.3157N, mg4=1.414N, mg5=1.512N, mg6=1.61N, mg7=1.708N, mg8=1.806N

Then I converted mm to m....0047, .0052, .0059, .0063, etc.

It's asking for k and in parentheses next to it has slope of graph. [ie k(slope of graph)] So k=slope of graph. Slope equals rise/run, (delta y)/(delta x). So I choose two points 1 & 4.

(1.12N - 1.414N) / (.0047m - .0063m) = -0.294N / -.0016m = 183.75 N/m.

His answer is k = 20. Where did go wrong to get a value so far from the answer?

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