On this day in physics: 07 January 1610 Galileo makes the first observation of four of Jupiter’s moons, which would be named the Galilean Moons after him (Source).
Word of the day: Velocity describes the rate at which an object is changing position, or moving through space, or any other medium. It can be described mathematically as v(t) or x'(t). x'(t) is said x-prime of t, which denotes that it is the derivative of the position vector. This is because the a derivative calculates the rate of change, and velocity is the rate of change of position. Velocity is also a vector quantity, meaning the direction of motion is also included in the information. The units for velocity are distance per time, in whatever unit you like. Common velocity units are miles per hour, meters per second, inches per second, kilometers per hour, the list goes on.
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Keywords: Position, Kinematics, Velocity, Physics, Podcast
