## amistre64 3 years ago When trying to find out a spring constant, should the platforms mass be included in the calculations if the scale has been zeroed out by the weight of the platform?

1. amistre64

|dw:1348234155317:dw|

2. Algebraic!

no

3. amistre64

my gut says no as well; but my physics teacher said that we have to.

4. mathslover

Yes same here... since : when you have already taken the mass including that of the platform mass as 0 , then we should not include the mass of the platform again.

5. RaphaelFilgueiras

the new deformation is caused only by new mass

6. RaphaelFilgueiras

so no

7. amistre64

|dw:1348234340830:dw| he "asked the math major" will the first point be at the origin. To which I stated, "hopefully".

8. RaphaelFilgueiras

you will read only \[\Delta x\]

9. mathslover

@RaphaelFilgueiras is right (acc. to me)

10. Algebraic!

so he wants you to find the slope of a line but he insists the y intercept matters...

11. Algebraic!

humor him I guess...

12. amistre64

the slope of the linear approximation is the spring constant. And that slope is not dependant on where you begin so long as the data points are in the proper relation

13. amistre64

i humored him .... i figure its best not to disrupt the delicate balance of the non math students of the class :)

14. amistre64

if the platform totally stretches out the spring, that might be a concern ... but wouldnt you just use a different platform?

15. Algebraic!

I guess he's technically right, since you could get into a region where the spring is non-linear ... but for practical purposes, kind of pointless extra busy work...

16. Algebraic!

pointless extra superfluous* busy work

17. amistre64

lol, sounds alot like number theory class this term too; alot of busy work to learn how to divide

18. Algebraic!

heh. busy work is a global constant.

19. amistre64

ive got another gripe that I will post anew ;)

20. mathslover

Go for it.. :)