If a mass of 3 kg is located at x₁ = 20 cm and a mass of 2 kg is located at x₂ = 45 cm, what is the x coordinate of the Center of Mass of the system?

a. 10 cm

b. 20 cm

c. 30 cm

d. 40 cm

e. 50 cm

If one mass of 1000 kg is moving at 80 m/s in the +x direction, and another mass of 2000 kg is moving at 100 m/s in the x direction, what is the velocity of the center of mass? Signs matter.

-60 m/s

a. -40 m/s

b. -20 m/s

c. +20 m/s

d. +40 m/s

e. +60 m/s

If a meter stick has length of 1 m and mass m_ms = 400 g, and the fulcrum is distance r₁ = 70 cm from its far left end, and a stack of coins of mass m₂ = 550 g is to the right of the fulcrum, how far should the coins be from the left end when the system is in equilibrium? Do not neglect the mass of the meter stick.

a. 45 cm

b. 55 cm

c. 65 cm

d. 75 cm

e. 85 cm