## anonymous 3 years ago Please help with the last part of the attached question. O_o

1. anonymous

2. anonymous

ok so at at the required moment of time!.. you see only 4 buckets contribute to the momentum .. !!

3. anonymous

@Mashy: Umm. I think only buckets 2,3 and 4 would produce a moment about the centre of the wheel. But I don't know how to calculate it.

4. anonymous

yes. 2,3,4 but not one. taking moment around the axis, $$\Sigma M= (W_2+W_3+W_4) \times 1.6m$$

5. anonymous

bucket 1 has force line distance to axis=0, the others have no force line.

6. anonymous

shadow thats wrong.. you cannot take 1.6m ..moment is calculate as the force multiplied by the perpendicular distance from the centre!!

7. anonymous

lol actually, yes, but to simplify calculations my teacher taught us a trick: to extend the force vectors and take the distance from the center. Yes, that's a lil' illegal, but it can simplify question sols like this one :P

8. anonymous

no.. i ll upload pic wiat!

9. anonymous

10. anonymous

and what you are saying is the CORRECT way of taking the perpendicular distance.. its not illegal.. its perfect!

11. anonymous

lol it is quite magical.

12. anonymous

@Mashy: Ok, so for x and z, I find the perpendicular distance by the formula sin45x1.6, right? And then multiply both of them by 400? For y, I simply multiply 1.6 by 400 to get the moment about the centre? Finally, I add the three values to get the resultant moment. Am I right so far?

13. anonymous

yup! :)

14. anonymous

Thank you so much @Shadowys ! :D

15. anonymous

you're welcome :)