Revolving doors are energy efficient, preventing drafts. They are also efficient from a traffic standpoint, allowing large numbers of people to enter the building.

Do revolving doors move clockwise or counter-clockwise? Why?

In this building, there are 4 compartments in the revolving doors. What fraction of a complete turn do the revolving doors make for 1 person to enter the building? For 2 people? For 3 people?

How many degrees (out of 360°) do the revolving doors rotate when 1 person enters the building? 2 people? 4 people? 8 people? 100 people?

These doors make 4 complete rotations in a minute. Assuming one person in each compartment, what is the maximum number of people that can enter the building through these doors in 30 minutes? In 60 minutes? How long would it take 100 people to go into or out of the building if all compartments were full?

How would changing the design of the doors to 3 compartments or 5 compartments affect the size of the compartments? Affect the flow rate through the doors?