Orbit — Science definition
Defined in 2 courses:
- A curved path arising from motion and gravitational interaction around a system. (Science 6: Matter, Energy & Earth Systems)
- A curved path under gravity; the net inward force changes the direction of motion. Inertia is not an outward force. (Earth & Space Science)
Where it is taught
- The Solar System, Gravity & Orbits — Earth, Moon, Sun & Space Models, Science 6: Matter, Energy & Earth Systems, Grade 6
- Gravity, Orbits & Tides — Earth, Moon & Solar System, Earth & Space Science, Grade 9
In use
Each planet moves sideways fast enough that it falls around the Sun rather than into it, which is all an orbit is.
The Solar System, Gravity & Orbits
In a circular orbit, the net acceleration points inward even when speed is constant.
Gravity, Orbits & Tides
Questions using orbit
Problem 1
Answer and explanation
Gravity supplies the changing direction in the basic orbit model; the statement removes the mechanism it needs.
Compare the scientific meaning and reasoning after an independent attempt. A different accurate supported response can be correct; human review is required.
Problem 2
- One illustrative result establishes every real condition and needs no further evidence.
- Gravity stops at the top of the atmosphere.
- A bright reflected object must be a star.
- orbit: A curved path arising from motion and gravitational interaction around a system.
Answer and explanation
orbit: A curved path arising from motion and gravitational interaction around a system.
A curved path arising from motion and gravitational interaction around a system. A is the better basic explanation. Gravity changes the moving satellite’s direction rather than vanish outside the atmosphere. Without the modeled force, its motion would not follow the same curved path around Earth. The drawing still omits precise speed, distance scale, and other influences needed for a full numerical prediction.
Problem 3
Answer and explanation
Gravity supplies the changing direction in the basic orbit model; the statement removes the mechanism it needs.
Compare the scientific meaning and reasoning after an independent attempt. A different accurate supported response can be correct; human review is required.
Problem 4
- Gravity alone holds them perfectly still
- Gravity continually changes the direction of their motion
- There are no forces acting on planets
- Planets have engines that keep firing
Answer and explanation
Gravity continually changes the direction of their motion
An orbit is the curved path created when an object's forward motion (inertia) is continuously bent by gravity's inward pull.