مفردات TOEFL

cloud of gas and dust in space

星云

move along a gravitationally bound path

绕轨道运行；环绕运行

move repeatedly about an equilibrium position

振荡；往复摆动

moving component fitting inside a cylinder

活塞

major nearly round body orbiting a star

行星

energy associated with position or configuration

势能

rate of energy transfer or work

功率

grooved wheel guiding a rope or belt

滑轮；带轮

send incident light back from a surface

反射

change light direction through change of optical medium

折射；使发生折射

strengthen a structure with added support or material

加固；增强结构强度

exert a force pushing an object away

排斥；产生斥力

enhanced response to driving near a natural frequency

共振

turn about an axis

旋转；使旋转

turning motion about an axis

旋转；自转

ratio of capacity to expected demand in design

安全系数

natural or artificial object orbiting a larger body

卫星

moon blocks part or all of sun from observers view

日食

sun and objects gravitationally associated with it

太阳系

mechanical disturbance traveling through a medium

声；声音

vehicle designed to travel or operate in space

航天器

rate of distance traveled without direction

速率；速度大小

self gravitating luminous body sustained by fusion during active life

恒星

force or action that a structure must support

结构荷载；结构载荷

powerful stellar explosion

超新星；超新星爆发

instrument collecting radiation from distant objects

望远镜

pulling force transmitted through a stretched member

张力；拉力

planet with a rocky solid surface

类地行星；岩质行星

turning effect of a force about an axis

力矩；转矩