when they meet the 40-kg boy will have moved a distance of 6 m.
Friction is the force that resists motion when the surface of one object comes in contact with the surface of another.
It is the average position of all the parts of the system, weighted according to their masses.
here,
masses of the boys
M=40 kg,
m=60 kg
x1 = 10 m
The displacement of the 40 kg boy is calculated from the principle of center mass.
XM = ( mx1 + Mx2) / ( m + M )
X(40) = (60 x 10 + 40 x 0) / (40 kg + 60 kg)
X(40) = (600)/(100)
X(40) = 6 m
X(60) = (60 x 0 + 40 x 10 m) / (40 kg + 60 kg)
X(60) = (400)/(100)
X(60) = 4 m
Thus,
when they meet the 40-kg boy will have moved a distance of 6 m.
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