Answer:
dJ = 1.7 m
Explanation:
The Equation of the Balancing the moments in the center of the seesaw is like this:
∑Mo = 0
Mo = F*d
Where:
∑Mo : Algebraic sum of moments in the center(o) of the balance
Mo : moment in the o point ( N*m)
F : Force ( N)
d : distancia of the force to the the o point ( N*m)
Data
mA = 60 kg : mass of the Anna
mJ = 70 kg : mass of theJon
dA = 2 m : Distance from Anna to the center of the seesaw
g: acceleration due to gravity
Calculation of the distance from Jon to the center of the seesaw (dJ)
∑Mo = 0 WA : Ana's weight , WJ : Jon's weight
W = m*g
(WA)(dA) - (WJ) (dJ) = 0
(mA*g)(dA) - (mJ*g)(dJ) = 0
We divide by g the equation:
(mA)(dA) - (mJ)(dJ)= 0
(mA)(dA) = (mJ)(dJ)
dJ = 1.7 m