Perpendicular line to a plane

I took this picture. It is of a radio that is used in the broadcasting industry. This shows a perpendicular line to a plane because the purple line is on the radio antenna and that is going through the plane which is the radio itself. The purple box is the plane. This is used everyday when the news needs to be told each day and the radio is listened to by many people in their cars on the way to work or different times throughout the day.