In a closed system, an object with a mass of 1.5 kg

collides with a second object. The two objects then move together at a velocity of 50 m/s . The total momentum of the system is 250 kg⋅m/s . What is the mass of the second object? (1 point)
Responses

3.0 kg
3.0 kg

1.5 kg
1.5 kg

3.5 kg
3.5 kg

5.0 kg

1 answer

To find the mass of the second object, we can use the principle of conservation of momentum.

The total momentum of a closed system before and after the collision remains the same. The momentum before the collision can be expressed as the sum of the momenta of both objects.

Given:

  • Mass of the first object (m1) = 1.5 kg
  • Final velocity of both objects after collision (v) = 50 m/s
  • Total momentum (P) = 250 kg·m/s

First, we calculate the total momentum after the collision:

\[ P = (m_1 + m_2) \cdot v \]

Where:

  • m2 = mass of the second object
  • v = final velocity = 50 m/s

Setting the total momentum equal to P:

\[ 250 \text{ kg·m/s} = (1.5 \text{ kg} + m_2) \cdot 50 \text{ m/s} \]

Now, we can solve for \( m_2 \):

  1. Divide both sides by 50 m/s:

\[ \frac{250 \text{ kg·m/s}}{50 \text{ m/s}} = 1.5 \text{ kg} + m_2 \]

\[ 5 \text{ kg} = 1.5 \text{ kg} + m_2 \]

  1. Solve for \( m_2 \):

\[ m_2 = 5 \text{ kg} - 1.5 \text{ kg} \]

\[ m_2 = 3.5 \text{ kg} \]

Therefore, the mass of the second object is 3.5 kg.