Question

two freight cars each with a mass of 3.0 * 10^5 kg collide and stick together. One was initially moving at 2.2 m/s, and the other was at rest. What is their final speed? Define the system as the two cars.​

Answer 1

1.1 m/s

Step-by-step explanation:

We know in an inelastic collision, applying the principle of conservation of momentum :-

• m₁v₁ + m₂v₂ = (m₁ + m₂)v

1. m₁ = mass of object 1 = 3 x 10⁵ kg
2. m₂ = mass of object 2 = 3 x 10⁵ kg
3. v₁ = initial speed of object 1 = 2.2 m/s
4. v₂ = initial speed of object 2 = 0 m/s (rest)
5. v = final combined speed = ?

Substituting the values

• 3 x 10⁵(2.2) + 3 x 10⁵(0) = (3 x 10⁵ + 3 x 10⁵)v
• 6.6 x 10⁵ = 6 x 10⁵ x v
• v = 6.6/6
• v = 1.1 m/s