A boy and girl are balanced on a "massless" seesaw. The boy has a mass of 75 kg and the girl a mass of 50kg. The seesaw is 6 meters in lenght with the pivot point between them...What are the distances each child must sit relative to the pivot point?

Question

amistre64 · Answer

what are your thoughts about it?

amistre64 · Answer

spose the boy is at 1 meter from the pivot,  how far does the girl have to be to balance out?

anonymous · Answer

1 meter from the pivot

amistre64 · Answer

no, a 50 girl does not balance out a 75 boy when they are equal distances from the pivot.

amistre64 · Answer

the force applied at a distance, is equal to Fd

75*1 = 50*d

when d=1, we have 75 = 50 which is just not correct

amistre64 · Answer

what value of d, makes 75 = 50d ?

anonymous · Answer

25

amistre64 · Answer

50*25 is not 75,  50 + 25 is....  but that is not the operation we are doing

50*75/50 = 75

so for every 1 meter the boy sits, the girl has to sit 75/50 meters to balance out

if the boy sits n meters, the girls sits 3/2 n meters, and their sum has to be equal to 6

n + 3/2n = 6

find n, and you can define their distances from the pivot

anonymous · Answer

so, 
n +3/2n =6
n=6/3/2
n=4