Siteadmin, Check users, nsTeam1RO, nsTeam1RW, nsTeam1_talkRO, nsTeam1_talkRW, oversight, Administrators
30,650
edits
Changes
Jump to navigation
Jump to search
Line 2:
Line 2: − The term "escape velocity" is sometimes used. This term is in error. Escape speed is a scalar, not a vector. An object in motion with respect to a celestial body need not be moving directly away from that body in order to escape it.+
Let's not quibble about synonyms: that's like arguing about mass and weight
== Concept ==
== Concept ==
Escape speed is a scalar, not a vector. An object in motion with respect to a celestial body need not be moving directly away from that body in order to escape it.
When an object is traveling exactly at escape speed, it is in a parabolic orbit with the body at the focus of the parabola. A parabolic path is open; hence an object following such a path will never return to the body.
When an object is traveling exactly at escape speed, it is in a parabolic orbit with the body at the focus of the parabola. A parabolic path is open; hence an object following such a path will never return to the body.