The momentum \( p \) of an object can be calculated using the formula:
\[ p = m \cdot v \]
where:
- \( m \) is the mass of the object (in kg),
- \( v \) is the velocity of the object (in m/s).
For a body with a mass of \( 2 , \text{kg} \) moving at a speed of \( 3 , \text{m/s} \):
\[ p = 2 , \text{kg} \cdot 3 , \text{m/s} = 6 , \text{kg m/s} \]
Therefore, the magnitude of the momentum is 6.0.