Question

The position vector of a particle of mass 3 kg is
r = 3 i + 3t j + 2t2 j and that of a particle of
A mass 5 kg isr2 = 3 i - 2t2 i - 6t 3, where t is
in s and r is in m. Determine the position of
the centre of mass of the system and the
velocity of the centre of mass at t = 2 s. 3

Answer 1

According to question
r1 = 3 i + 3t j + 2t^2 k
And
r2 = 3 i - 2t^2 - 6t^3 k

Thus r =  r1 . r2
            = root [ 9 - 6t^3 - 12t^5 ]