(1) The resulting velocity of both train cars after they hit is 10 m/s.
(2) The momentum of the first train before and after collision is 12,500 kgm/s and 5,000 kgm/s respectively.
The given parameters;
(1)
The final velocity of the both trains after the collision is obtained by applying the principle of conservation of linear momentum for inelastic collision.
m₁u₁ + m₂u₂ = v(m₁ + m₂)
where;
v is the final velocity of the two trains after collision.
The resulting velocity of both train cars after they hit is calculated as
(500 x 25) + (750 x 0) = v(500 + 750)
12500 = 1250v
[tex]v = \frac{12500}{1250} \\\\v = 10 \ m/s[/tex]
(2)
The momentum of the first train before collision;
[tex]P_1 = m_1 u_1\\\\P_1 = 500 \times 25\\\\P_1 = 12500 \ kg.m/s[/tex]
The momentum of the first train after collision;
[tex]P_1_f = m_1 v\\\\P_1_f = 500 \times 10\\\\P_1_f = 5,000 \ kg.m/s[/tex]
The momentum of the second train before collision;
[tex]P_2 = m_2 u_2\\\\P_2 = 750 \times 0\\\\P_2 = 0 \ kg.m/s[/tex]
The momentum of the second train after collision;
[tex]P_2_f = m_2 v\\\\P_2_f = 750 \times 10\\\\P_2_f = 7,500 \ kg.m/s[/tex]
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