A

David

Darling

speed

Speed is the ratio of the distance traveled by an object to the time it takes. No direction is specified, which means that speed is a scalar quantity. Velocity, by constrast, is a vector. Units of speed are meters per second (m/s), kilometers per hour (km/h), miles per hour (mph), ffeet per second (f/s), etc. Average speed is given by total distance covered divided by total time taken.