welcome to our fourth example video. Looking at the microscopic and macroscopic picture of the kinetic theory of of T equals 25 degrees Celsius air at one atmosphere And this video, we're going to ask ourselves how much time is there in between each collision? So how much time do we have in between a part of one particle colliding with another? We know that they're moving pretty fast and we know that the mean free path is quite small. So how do we do this? Well, we're going to do it with fundamental Kinnah Matics. We know that V is equal to Delta X over Delta T solving for Delta T then is going to be equal to how far they travel at that particular speed. So for us, that's going to be the mean free path length divided by the velocity which is going to be V. R. M s so we can go ahead and type that in for us. That was 0.23 times 10 to the negative 6 m, divided by V RMS, which was 200. And let's see here 266 meters per second and when you can type that in. You see, you really have a 10 to the negative six. And down here we have a 10 squared. So this is going to end up being a very small number indeed. In fact, this is 10 to the negative seven. So we're gonna end up with something on the order of 10 to the negative. Nine seconds in between every collision. So about every nanosecond. And an individual particle of air is having a collision with another particle.