radian
radian — 名詞
- radiansingular
- radiansplural
1. a unit for measuring angles in mathematics and physics, based on the radius of a
弧度
以半徑測量角度的單位
a unit for measuring angles in mathematics and physics, based on the radius of a circle. One radian is the angle size you get when the arc (the curved part of the circle's edge) and the radius that reaches out from the centre are the same length. A full circle contains about 6.283 (2π) radians.
Talia set her calculator to radians before working on the trigonometry problems.
Talia 在解三角函數題目前，先把她的計算機設為弧度模式。
collocation: set [calculator] to radians
A full circle measures 2π radians, which is equal to 360 degrees.
一個完整的圓是 2π 弧度，相當於 360 度。
conversion: radians ↔ degrees
Professor Asher asked the class to convert 45 degrees into radians for the exercise.
Asher 教授要求全班將 45 度換算成弧度作為練習。
The engineering formula uses radians, so Salma had to switch her calculator mode before starting.
這個工程公式使用弧度單位，所以 Salma 必須先切換計算機模式才能開始計算。
When the arc length equals the circle's radius, the angle formed is exactly one radian.
當弧長等於圓的半徑時，所形成的角度恰好是一弧度。
用法筆記
Most scientific calculators have a 'RAD' or 'rad' mode for angle input. Many mathematical formulas, especially in calculus and physics, naturally work best with radians rather than degrees.