# If three ideal gases collide with each other, how will the second one travel?

##### 1 Answer

With accelerated velocity.

An **ideal gas** is considered to be a point mass with negligible volume compared to its container. So, we neglect all degrees of freedom but those of *linear motion*. As a result, we assume the gas does not rotate or vibrate, but only moves in a **straight line**.

However, they are also said to **collide elastically**, i.e. perfect transfer of kinetic energy (

As a result, an ideal gas in the middle of two others **receives additional kinetic energy**, which goes into increasing its velocity.

(If you closely in the above diagram, that is precisely what occurs.)

*Thus, an ideal gas that was hit by another one, that consequently collides into a third, had traveled with an accelerated velocity imparted by the first ideal gas.*