Physical Barriers
As physical obstacles, we can enumerate all those physical barriers that block the action and prevent the progress or the achievement of a concrete goal. Examples:
- architectural barriers that hinder access to people with reduced mobility;
- doors, gates, and access control systems, designed to keep intruders or attackers out;
- large objects, fallen trees or collapses through passageways, paths, roads, railroads, waterways or airfields, preventing mobility;
- sandbanks, rocks or coral reefs, preventing free navigation;
- hills, mountains and weather phenomena preventing the free traffic of aircraft;
- meteors, meteorites, micrometeorites, cosmic dust, comets, space debris, strong electromagnetic radiation or gravitational field, preventing a spacecraft from navigating freely in space.
Read more about this topic: Obstacle
Famous quotes containing the words physical and/or barriers:
“The term preschooler signals another change in our expectations of children. While toddler refers to physical development, preschooler refers to a social and intellectual activity: going to school. That shift in emphasis is tremendously important, for it is at this age that we think of children as social creatures who can begin to solve problems.”
—Lawrence Kutner (20th century)
“Developing the muscles of the soul demands no competitive spirit, no killer instinct, although it may erect pain barriers that the spiritual athlete must crash through.”
—Germaine Greer (b. 1939)