Question

Valeria rolls a 5.0-kg red bocce ball down the lane for the Bocce Ball league championship. One blue ball is in her way and Valeria hits it head-on with a velocity of 9.0 m/s (red ball). Valeria's red ball acquires a new velocity of 7.0 m/s. What is the velocity of the blue bocce ball?

Answer 1

The mass of a bocce ball, m=5.0 kg

The initial velocity of the red ball, u=9.0 m/s

The velocity of the red ball after the collision, v₁=7.0 m/s

The mass of the blue ball will be the same as the red ball. And let us assume that the blue ball will be zero before the collision, i.e., it was at rest before the collision.

From the law of conservation of momentum, the total momentum of a system will always remain constant.

Thus,

`\begin{gathered} mu=mv_1+mv_2 \\ u=v_1+v_2 \end{gathered}`

Where v₂ is the velocity of the blue ball after the collision.

On substituting the known values,

`\begin{gathered} 9.0=7.0+v_2 \\ v_2=9.0-7.0=2.0\text{ m/s} \end{gathered}`

Thus the velocity of the blue ball after the collision is 2.0 m/s.