a 0.199 kg snowball moving west makes an inelastic collision with a 2.89 kg box moving 0.523 m/s west. afterward,they move west at 1.92 m/s. what was the initial velocity of the snowball? PLEASE HELP MEEEEE

Respuesta :

Answer:

The initial velocity of the snowball was 22.21 m/s

Explanation:

Since the collision is inelastic, only momentum is conserved. And since the snowball and the box move together after the collision, they have the same final velocity.

Let [tex]m_1[/tex] be the mass of the ball, and [tex]v_1[/tex] be its initial velocity; let [tex]m_2[/tex] be the mass of the box, and [tex]v_2[/tex] be its velocity; let [tex]v_f[/tex] be the final velocity after the collision, then according to the law of conservation of momentum:

[tex]m_1v_1+m_2v_2=v_f(m_1+m_2)[/tex].

From this we solve for [tex]v_1[/tex], the initial velocity of the snowball:

[tex]\boxed{v_1=\frac{v_f(m_1+m_2)-m_2v_2}{m_1}}[/tex]

now we plug in the numerical values [tex]m_1=0.199\:kg[/tex], [tex]m_2=2.89\:kg[/tex], [tex]v_2=0.523\:m/s[/tex], and [tex]v_f=1.92\:m/s[/tex] to get:

[tex]v_1=\frac{1.92*(0.199+2.89)-2.89*0.523}{0.199}[/tex]

[tex]\boxed{v_1=22.21\:m/s}[/tex]

The initial velocity of the snowball is 22.21 m/s.

P.S: we did not take vectors into account because everything is moving in one direction—towards the west.