When you open two windows on opposite sides of a room there will be a draft going through the room. What dictates the direction of that draft?

Question

I often open my balcony door and my front door to let fresh air into my apartment. I’ve noticed that the draft almost always flows from the balcony and out the front door. Shouldn’t the direction be random?

In: Physics

Answer 1

It’s pressure. Fluids, in this case air, move from an area of high pressure to an area of low pressure. It’s the same way wind is created, in this case you’re creating wind in your house be connecting areas of different pressure.