مفردات TOEFL

rate of change of velocity with time

加速度

relating to sound and its properties

声学的；声音的

maximum wave or oscillation departure from equilibrium

振幅

curved structure transmitting loads to side supports

拱；拱形承重结构

join separate parts to make a complete device

装配；组装

exert a force drawing an object closer

吸引；产生吸引力

angle between rotation axis and orbital plane normal

转轴倾角；自转轴倾角

line about which a body rotates

轴；自转轴

shaft supporting a rotating wheel or part

轴；车轴

elongated structural member carrying crosswise loads

梁

region with event horizon from within which light cannot escape

黑洞

inward net force component for curved motion

向心力

structural member carrying mainly axial compression

柱；承重柱

pressing together under inward forces

压缩；受压

allow electric current to pass through

导电；传导电流

material that readily allows electric current

导体

principle that total energy of isolated system is constant

能量守恒

requirement or limit restricting engineering options

设计约束；设计限制条件

wave spreading near obstacles or openings

衍射

measurable extent such as length width or height

尺寸；维度

directed change from initial to final position

位移

reflected sound heard separately after original

回声

physical property responsible for electrical interactions

电荷

interconnected electrical components forming a current path

电路

rate of electric charge flow

电流

machine converting electrical energy to mechanical motion

电动机

opposition to electric current related to voltage and current

电阻

physical quantity transferred as work or heat

能量

useful service or output relative to energy input

能源效率；能效