Dunkirk: Where History Happened. We visit 10 places connected with the remarkable evacuation of the British Expeditionary Force from northern France in 1940. This feature was first published in the April 2010 edition of BBC History Magazine. Tuesday 25th May 2010.
The seepage velocity is less than the actual flow rate of the liquid or gas in the pores because the fluid moves only through the portion of the cross-sectional area S that is occupied by the pores.
r = d / twherer is the rate, or speed (sometimes denoted as v, for velocity, as in this kinematics article)d is the distance movedt is the time it takes to complete the movement. By Andrew Zimmerman Jones. Definition: Distance travelled per unit time. Speed is the scalar quantity that is the magnitude of the velocity vector. The most common way to calculate the constant velocity of an object moving in a straight line is with the formula: r = d / t. where.