Changing levels of certain substances in the blood, such as sodium, can cause confusion. Increased heart rate...heart palpitations, which feel like your heart is racing or throbbing. To make up for the loss in pumping capacity, the heart beats faster.
The pitch plane of a pair of gears is the plane perpendicular to the axial plane and tangent to the pitch surfaces. A pitch plane in an individual gear may be any plane tangent to its pitch surface.
Two or more gears working in a sequence (train) are called a gear train or, in many cases, a transmission; such gear arrangements can produce a mechanical advantage through a gear ratio and thus may be considered a simple machine. Geared devices can change the speed, torque, and direction of a power source.