### motivation:

Impulse
* are drives
  - infinite in number and vary within each individual
  - shocks that get things rolling
  - signals of information
  - thoughts in transmission over the nervous system
  - vital urges, animal pulsations, directed at satisfaction of body needs
* arising from a temperature sense organ in the skin can stimulate sweating.
* cause peristaltic contraction of the ducts in the testis, epididymus, and the vas.
* created by abuse are encoded in their brains.
* enter the cen- tral nervous system through the afferent fibers of the peripheral nerves.
* form only at the nodes - and propagate by jumping from one node to the next.
* go from there to the olfactory bulb in the brain.
* is average force multiplied by the time that force acts
  - change in momentum due to collision
  - defined in classical mechanics as a force multiplied by the amount of time it acts over
  - equal to momentum change
  - force multiplied by time
  - measured by the force multiplied by the change in time
  - product of average force and elapsed time
  - the change in momentum
* is the integral of force over time, it is measured in Newton-seconds
* is the product of force time during which the force is applied
  - the applied force and the time over which that force is applied
* measurement of how much force a rocket motor makes and for how long.
* originate in the eccentric cell when the cell is stimulated by light.
* pass down the axon to the dendrites of other neurons
  - through sensory sytem to both hypothalamus and cerebral cortex
* travel even faster if neuron has myelin insulation
  - through nerves because of ions
* travels electrochemically along axons and chemically across synapses as neurotransmitter.
* vector also, in the direction of the force.
+ Specific impulse, General considerations: Spaceflight :: Mechanics
  * There are two ways people find the number for specific impulse. To find the specific impulse, one divides the impulse by the amount of fuel. Impulse is a measurement of how much force a rocket motor makes and for how long. A motor that makes a low force for a long time can sometimes have a higher impulse than a motor that makes a high force for a short time. The amount of fuel used to find specific impulse can be measured in different ways. It is sometimes measured in mass and sometimes in weight. When the amount of fuel is measured in mass, the specific impulse is expressed as a speed. This is usually in meters per second.

### motivation | impulse:

Action potential
* are all or none, meaning, all action potentials have the same magnitude
  - essentially digital signals which encode information as a temporal sequence
* are generated by the activation of certain voltage-gated ion channels
  - that move from the tentacles to the leaf surface
  - of relatively long duration compared to neuronal action potentials
  - only there to open voltage-gated calcium channels and allow calcium influx
* can regenerate itself along the neuron.
* cause the release of neurotransmitters when they reach the end of an axon a.
* causes the release of neurotransmitter.
* is an impulse
  - nerve impulses
* require a. sodium ions.
* start where the dendrites and axon meet.

Electrical impulse
* are what keep a healthy heart beating at a normal rate and rhythm.
* stimulate the facial muscles safely
  - muscle of the stomach, leading to better stomach function

Impulse control
* is based on prediction.
* means using problem-solving skills.
* well-documented casualty of low serotonin.