## Bbambino1976 2 years ago This is the deal, I have two pulleys with a radii of 10.0in. and 6.00in., and their centers are 40.0 in. apart. If the pulley belt is uncrossed, what must be the length of the belt? Can somebody pull me to the side and please explain this to me, I also have a couple questions about this.

1. Jbo11

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2. Jbo11

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3. Jbo11

if so, here is a great step by step explanation http://frentzandsons.com/Hardware%20References/tofindthebeltlength.htm

4. Bbambino1976

thank-you very much.

5. Jbo11

ok maybe bad example So in this you have two circles, you need to know the equation for the circumference of the circle which is 2pir^2 and use only half because the belt covers only half the circles then add the middle which is 40 but times by two because there's two lengths of it

6. Bbambino1976

before you go any farther, that site you gave to my is great. I've got the belt length needs to be 81.57inches. Did I do it right?

7. Jbo11

I got 131.2

8. Jbo11

so you use the diameters which are twice the radii so 20 and 12 add them, then multiply by 1.6, then add 40 twice

9. Bbambino1976

thats what i did wrong. i put the radii , not the diameter.

10. Jbo11

ah, yup, well as long as you understand the problem, little fixes like that can be checked and fixed

11. Bbambino1976

so how does the equation go??

12. Bbambino1976

13. Jbo11

yea

14. Bbambino1976

drum roll please........... I got belt length of 113.5in.

15. Bbambino1976

pellet it's not the same, what did I do wrong?

16. Jbo11

17. Bbambino1976

Would'nt you call that the circumference

18. Jbo11

yup, you are using half the circumference and then adding the length between the two pullys

19. Bbambino1976

half the circumference of each pully, so it be 32radii?

20. Jbo11

yea then times 1/2pi and add 80 gives you 131.2

21. Bbambino1976

thank-you so much.but I'm getting 130.27

22. Bbambino1976

I just recalculated and came up wth 131.2