Two objects are rolling towards one another. Object 1 has a mass of 10 kg and a velocity of 1.2 m/s.

To find the total amount of momentum after the collision, we first need to calculate the total momentum of the two objects before the collision.

The momentum (p) of an object is given by the formula:

\[ p = m \times v \]

Where:

• \( m \) is the mass of the object
• \( v \) is the velocity of the object

Step 1: Calculate the momentum of each object before the collision

For Object 1:

• Mass (\( m_1 \)) = 10 kg
• Velocity (\( v_1 \)) = 1.2 m/s

\[ p_1 = m_1 \times v_1 = 10 , \text{kg} \times 1.2 , \text{m/s} = 12 , \text{kg m/s} \]

For Object 2:

• Mass (\( m_2 \)) = 5 kg
• Velocity (\( v_2 \)) = -2.2 m/s (the negative sign indicates the opposite direction)

\[ p_2 = m_2 \times v_2 = 5 , \text{kg} \times (-2.2 , \text{m/s}) = -11 , \text{kg m/s} \]

Step 2: Calculate the total momentum before the collision

Now, we can find the total momentum (P_total):

\[ P_{\text{total}} = p_1 + p_2 = 12 , \text{kg m/s} + (-11 , \text{kg m/s}) = 12 - 11 = 1 , \text{kg m/s} \]

Conclusion

Since momentum is conserved in collisions, the total momentum after the collision will also be the same as before the collision. Therefore, the total amount of momentum these objects must have after they collide is:

1 kgm/s

Thus, the correct answer is \( \text{1 kgm/s} \).