Question

Two bodies of masses 10kg and 2kg are moving with velocities
2i - 7j + 3k and -10i + 35j -3k m/s respectively. Find the velocity of the centre of mass of the system.

Answer 1

m1=10kg
m2=2 kg
V1=2i-7j+3k m/s
V2=-10i+35j-3k m/s
Velocity of center of mass= (m1v1+m2v2)/(m1+m2)
=[10(2i-7j+3k)+2(-10i+35j-3k)]/(10+2)
=(20i-70j+30k-20i+70j-6k)/12
=(0i+0j+24k)/12
=24k/12=2k.