Question

A see-saw 8m long is balanced in the middle. Two children of mass 30kg and 40kg are sitting on the same side of fulcrum at a distance of 1.5m and 3.5m .Where must a lady weighing 60kgf sit from fulcrum so as to balance the see- saw

Answer it ASAP
i'm not getting the right ans. ​

Answer 1

l=8m

m1=30

m2=40

m3=60

x1=1.5

x2=3.5

let the fulcrum lie at the centre  (it has to lie there...LOL)

let the lady sit at a dis y from fulcrum

therefore by conserving net angular momentum

30*10*1.5+40*10*3.5-60*10*y=0

(we multiplied the masses with 10 so as to get weight)

300*1.5+400*3.5=600y

6y=4.5+14

y=18.5/6

y=3.08

therefore the lady should sit at a distance of 3.08 from the fulcrum (the fulcrum at the centre LOL) on the opposite side.

hope this helps