SAT词汇的掌握是大家取得SAT考试好成绩的基础，今天小编为大家提供了有关物理学的词汇，以下是详细内容。

　　Vector

　　A vector quantity, or vector, is an object possessing, and fully described by, a magnitude and a direction. Graphically a vector is depicted as an arrow with its magnitude given by the length of the arrow and its direction given by where the arrow is pointing.

　　Velocity

　　A vector quantity defined as the rate of change of the displacement vector with time. It is to be contrasted with speed, which is a scalar quantity for which no direction is specified.

　　Vertex

　　The center of a mirror or lens.

　　Virtual image

　　An image created by a mirror or lens in such a way that light does not actually come from where the image appears to be.

　　Uncertainty principle

　　A principle derived by Werner Heisenberg in 1927 that tells us that we can never know both the position and the momentum of a particle at any given time.

　　Uniform circular motion

　　The motion of a body in a circular path with constant speed.

　　Unit vector

　　A unit vector is a vector with length 1.

　　Universal gas constant

　　Represented by R = 8.31 J/mol · K, the universal gas constant fits into the ideal gas law so as to relate temperature to the average kinetic energy of gas molecules.