I was reading this wikipedia article on traffic theory https://en.wikibooks.org/wiki/Fundamentals_of_Transportation/Traffic_Signals. And it seems to outline an equation that computes the time a car stays in a queue behind a light
t = (p*r)/(1-p)
Where t is the queueing delay, p is arrival_rate / departure_rate and r is red time.
This seems to imply that when the rate of incoming traffic is higher than the rate of outgoing traffic, the resulting queueing delay is fixed. How can this be true? Won't the queue keep getting bigger and bigger if cars approach the intersection faster than they leave?
I'm not sure what tag to use for this question, so I apologize if the tags don't not fit the question.