Given a 60-μC point charge located at origin, find the total electric flux passing through the plane z = 26 cm.
The Attempt at a Solution
Since electric flux lines from a point charge emanate in every possible direction, only a quarter of these should be passing through the plane which is "above" the point charge. So the flux should be 15-μC. But the answer given in my textbook is 30-μC. Half the total electric flux. I can't figure out why it's only half, because there are going to be a lot of flux lines parallel to the plane. When I asked my teacher about this he told me that it's half because parallel lines meet at infinity - which is something I've never heard of before - further aggravating my confusion...
I'll very much appreciate any help. Thank you for reading.