rotation
part of speech
noun (a rotation, rotations; rotation as uncountable)
meaning for a pupil
1) Rotation is turning around a centre point or a line: "the rotation of the Earth". tree →
2) A rotation is one complete turn: "the wheel makes 10 rotations a minute". tree →
3) In maths, a rotation is a turn of a shape around a fixed point by an angle, such as a quarter turn (90 degrees). tree →
4) Rotation is taking turns in a fixed order: "we do the jobs in rotation". tree →
5) Crop rotation is growing different crops in a field each year to keep the soil healthy. tree →
sense in the lessons
In maths, rotations are given by an angle (90, 180, 270 or 360 degrees), a direction (clockwise or anticlockwise) and a centre of rotation; rotational symmetry means a shape looks the same after part of a turn. In science, the Earth's rotation on its axis makes day and night, taking about 24 hours. In PE and school jobs, things done in rotation are shared fairly. Phrases: rotation of the Earth, in rotation, quarter rotation, rotational symmetry, crop rotation.
examples
- The rotation of the Earth gives us day and night. tree →
- One full rotation of the Earth takes about 24 hours. tree →
- Rotate the triangle 90 degrees clockwise about point A. tree →
- A full rotation is 360 degrees; a half rotation is 180 degrees. tree →
- The wheel made 50 rotations in a minute. tree →
- We take the class jobs in rotation. tree →
- Farmers use crop rotation to keep the soil rich. tree →
note
Verb: rotate. Do not mix up rotation (spinning on its own axis: Earth, one day) and revolution or orbit (going around something else: the Earth around the Sun, one year). In maths, a rotation keeps the shape's size and form; only its direction changes. Anticlockwise (UK) = counterclockwise (USA).
In the corpora
Trees and pragmatics
Every meaning and example of «rotation» parsed by Mova, each sentence with its dependency tree and frames.