How is the coefficient of restitution zero for this problem?

[Benjamin_harsh]

Homework Statement

A mass $m_{1}$ of 100kg travelling with a uniform velocity of 5m/sec
along a line collides with a stationary mass $m_{2}$ of 1000kg. After the
collision,both the masses travel together with the same velocity.
The coefficient of restitution is zero.

Relevant Equations

$coefficient\; of \;restitution = \large\frac{Relative\; speed \;after \;collision}{Relative\; speed\; before\; collision} \normalsize= 0$

$coefficient\; of \;restitution = \large\frac{Relative\; speed \;after \;collision}{Relative\; speed\; before\; collision} \normalsize= 0$

 

[Baddum12]

There is enough information in the problem to explicitly calculate. Think of what the relative speed after collision is.

 

[Merlin3189]

How is the coefficient of restitution zero for this problem?

1- The question tells you it is zero.
2- The relative velocity after collision is zero. So the formula, $CR=\frac{RV_{after}}{RV_{before}}$ also tells you CR is zero.

The two objects collide and stick together.

 

[Benjamin_harsh]

2- The relative velocity after collision is zero. So the formula, $CR=\frac{RV_{after}}{RV_{before}}$ also tells you CR is zero.

What values should I substitute in $RV_{after}$ and $RV_{before}$?

 

[Merlin3189]

Sorry, I don't like to do maths .
The value you should substitute for $RV_{after}$ is the relative velocity after they collide.
So the physics question is, "what is the relative velocity after collision?"
If you know what relative velocity means, then the question tells you this explicitly (in different words.)

Do you understand relative velocity?