contestada

Three identical train cars, coupled together, are rolling east at speed v0. A fourth car traveling east at 2v0 catches up with the three and couples to make a four-car train. A moment later, the train cars hit a fifth car that was at rest on the tracks, and it couples to make a five-car train.

What is the speed of the five-car train?

Express your answer in terms of v0

Respuesta :

opudodennis

Answer:

[tex]1v_0[/tex]

Explanation:

Assuming that cars 4 and 5 have same mass so that the momentum  

P=mv where m is mass and v is velocity hence

Momentum=0+2mv+3mv=5mv

The final mass is 2m+3m=5m

From aw of conservation of momentum

[tex]5mv_0=5mv[/tex] hence [tex]v=1v_o[/tex]

Therefore, the speed is [tex]1v_0[/tex]

Otras preguntas