How much memory will an iPhone time lapse take up?

Lets say I record in time lapse mode for 1 hour, how much memory will it take up?
I'm sure the final result will probably only last for 40-60 secs, does that mean itl only take up a few mb?

Well you can do the math.

Using the file manager on the camera, see how large each image file is.

Using that number, you can see how large the time lapse video will be. One minute of time lapse video will use 1440 frames per minute if you play it back at 24 fps (cine)

Your video will only require the memory for the shortened version, not the entire 1 hour version. It'll take the same amount of memory as if you recorded a normal video of 40-60 seconds -- not very much.