Considering conservation of momentum;
m1v1 + m2v2 = m3v3
In which,
m1 = mass of snowball 1 = 0.4 kg
v1 = velocity of snowball 1 = 15 m/s
m2 = mass of snowball 2 = 0.6 kg
v2 = velocity of snow ball 2 = 15 m/s
m3 = combined mass = 1 kg
v3 = velocity after comination
Therefore;
0.4*15 + 0.6*15 = 1*v3
v3 = 6+9 = 15 m/s
KE = 1/2mv^2
Then,
KE1 = 1/2*0.4*15^2 = 45 J
KE2 = 1/2*0.6*15^2 = 67.5 J
KE3 = 1/2*1*15^2 = 112.5 J
Therefore, KE3 (kinetic energy after collision) = K1+K2 {kinetic energy before collision). And thus it is 100%.
I think force is something to do with a force being applied to a movement or is just to pull but not sure sorry if this aint right
Here since both children and merry go round is our system and there is no torque acting on this system
So we will use angular momentum conservation in this
now here we have
Now when children come to the position of half radius
then we will have
now from above equation we have
