Respuesta :
Answer:
The common velocity of truck v = 2.759 m/s
Explanation:
Given that,
Mass of first railway truck, M = 800 Kg
Mass of second railway truck, m = 650 Kg
Velocity of first railway truck, U = 5 m/s
Velocity of second truck, u = 0 m/s
According to the conservation of linear momentum,
The total momentum after impact = total momentum before impact
The mass of the truck remains the same, but the velocity after impact is coupled to be v.
Therefore,
          Mv + mv  =  MU + mu
             v (M+m) = MU   (u = 0)
             v = MU/(M+m)
Substituting the values in the above equation,
             v = 800 Kg x 5 m/s  /  (800 Kg + 650 Kg)
             v = 2.759 m/s
Hence, the common velocity of the coupled tucks moving off after collision is v = 2.759 m/s
