At an instant when a particle of mass 80 g has a velocity of 25 m/s in the positive y direction, a 75-g particle has a velocity of 20 m/s in the positive x direction. What is the speed of the center of mass of this two-particle system at this instant?
1) 16 m/s
2) 45 m/s
3) 23 m/s
4) 20 m/s
5) 36 m/s
Answer: 1
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