Sophia (mass 47Kg) is travelling to the right with a velocity of 7.2m/s and Neesha (mass 68Kg) is travelling to the left with a velocity 4.8m/s. When they meet, they hold hands and travel off together. Give their final velocity and direction
We know that p=mv,
So Sophia travels at 7.2 m/s and she has a mass of 47kg so her p is: p=7.2 x 47=338.4 kgm/s
Neesha travels with a velocity of -4.8 m/s and she has mass of 68kg, so her p is: p= -4.8 x 68= - 326.4 kgm/s
Pinitial=pfinal
ps + pn= mfinal x vfinal
338.4 +(-326.4)=(47+68) x vfinal
12= 115vfinal, vfinal=0,1m/s
As our velocity is positive, the direction is right.
RL
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