Question

In an arrangement of two wheel and axle systems, the radii of wheels are 20 cm and 15 cm and the radii of axle are 4 cm and 3 cm. Calculate E if L = 540 kg.

Answer 1

Let `MA_(1)` and `MA_(2)` be the mechanical advantages of the upper and lowers wheel and axles, respectively
`MA_(1)=(L_(1))/(E_(1))=(R_(1))/(r_(1) ) " " (1)`
Where ` L_(1)=540 kg wt`, `R_(1)=20 cm , r_(1)=4 cm`
`MA_(2)=(C_(2))/(E_(2))=(R_(2))/(r_(2))`
` = (E_(1))/(E_(2))=(R_(2))/(r_(2)) " " (2)`
From (1) `(540)/(E_(1))=(20)/(4)`
`E_(1)=(540)/(5)=108 kg wt`
`:.` From (2) `(108)/(E_(2))=(15)/(3) rArr (108)/(E_(2))=5`
`E_(2)=(108)/(5)=21.6 kg`
` wt = 21.6 xx 9.8 = 211.68 N`