1 If a lot of blood leaks out, it can cause a buildup of pressure in the brain because the brain is enclosed in the skull. There is no room for brain tissue to expand, and so the leaked blood can compress and kill important areas of the brain.  Hemorrhagic strokes tend to be more serious than ischemic strokes.
Horizontal definition, at right angles to the vertical; parallel to level ground. See more.
Quick Answer. In projectile motion, horizontal velocity is the rate at which an object is traveling parallel to the earth. Scientists calculate horizontal velocity using the formula v = d/t, the same formula used to determine the speed of an automobile. In projectile motion, horizontal velocity does not change; however, the forces of gravity give the object vertical acceleration, causing it to stop when it hits the ground.