A2.00-m rod of negligible mass connects two very small objects at its ends. the mass of one object is 1.00 kg and the mass of the other is unknown. the center of mass of this system is on the rod a distance 1.60 m from the 1.00-kg mass object. what is the mass of the other object?

The mass of the unknown body is 4.00 kg

Explanation:

To solve the problems within the masses we must set a reference system, we will place it in the unknown mass. The equation for the center of masses

      Xcm = ∑ Xi mi / Mt

With xi the distance from the reference system, mi body mass and Mt all masses.  

In our case

      m1 0 1.00 kg

      Xi = 2.00 m

The unknown body is on the reference system

      m2 =?

      X2 = 0 m

We calculate the position of the mass center for our reference system

      Xcm = 2 -1.6

     Xcm = 0.400 m

We substitute and calculate

     Xcm = m1 X1 / (1 + m2)

    (1 + m2) = m1 X1 / Xcm

    (1 + m2) = 1.00 2.00 / 0.4.00

    (1 + m2) = 5.00

    m2 = 5.00 -1

    m2 = 4.00 Kg

The mass of the unknown body is 4.00 kg

the chart show the masses and velocities of two colliding objects that stick together after a collision.

according to the law of conservation of momentum, the momentum of the object after the collision is  

answer

1,500

kg • m/s.