Question

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?

a. 16 m/s
b. 45 m/s
c. 23 m/s
d. 20 m/s
e. 36 m/s

Answer 1

16 m/s

Step-by-step explanation:

Given that

y momentum = 0.080 *25 = 2

x momentum = 0.075*20 = 1.5

total momentum = √(4 + 2.25)

Total momentum = √6.25

Total momentum = 2.5

total mass = mass of x and y momentum = 0.075 + 0.080 = 0.155

speed of mass center = total momentum / total mass = 2.5/0.155 = 16.

And thus, the speed of the center of mass of this two-particle system at this instant is 16 m/s