Showing my ignorance (too much NFL)

[mikesears]

I apologize for asking such a basic question but I don't watch too many teams attempt long field goals so here goes.

4th and 15, team A has ball on 27 yardline. They decide to attempt a Field Goal. The attempt is no good and does not break the plane of Team B's goal line (it becomes dead at Team B's 4 yardline. Where is the ball spotted for the new series for Team B and why?

I do know that if the attept is from inside the 20 and it breaks R's goalline and is no good, it goes to the 20 because it is a touchback.