下载APP
【单选题】
下列关于渐开线齿轮啮合角的描述，不正确的是（ ）。
A.
啮合角的大小在啮合过程中是不断变化的
B.
啮合角的大小恒等于两齿廓的节圆压力角
C.
啮合角的大小在啮合过程中是不变化的
D.
啮合角是指啮合线与两节圆的公切线所夹的锐角
参考答案：
参考解析：
刷刷题刷刷变学霸
举一反三
【单选题】Passage 3 Questions 11 to 15 are based on the following passage: Scientists in India have invented a new way to produce electricity. Their invention does not get its power from oil, coal or other fuel...
A.
Because bullocks have long been used by Indian people
B.
Because bullocks walk slowly and are easy to control.
C.
Because there are few non-working bullocks in India
D.
Because there is not enough oil in India.