# Physics of power

## Definitions

• Vector. A vector is a straight line from point A to point B, such as the line your fist travels when moving from your hip to an opponent's chin. Any deviation from the straight line will result in a loss of power.
• Displacement. Displacement is how far the fist is displaced from the hip to the chin along a vector.
• Distance. Distance is how far the fist actually travels during the punch, which includes any stray movements from the vector and its return travel back to the hip.
• Speed. Speed of the fist is measured using the distance it moves, which includes any extraneous movements away from the vector. Velocity is measured using displacement of the fist, which only uses travel along the vector and in only one direction.
• Velocity. Velocity of the fist = displacement of the fist  / time required to complete the displacement
• Acceleration. Acceleration of the fist  = change in velocity of the fist / time required to achieve the final velocity.
• Force. Force of the fist = mass of the fist (including arm and some of torso) x acceleration of the fist. As it applies to the punch, force is of no concern if it misses the chin. If it strikes the chin, then an important consideration is the amount of pressure the fist applies to the chin.
• Pressure. Pressure of the punch = force of the fist / striking area of the fist. Thus, the smaller the striking area of the fist, such as the first two knuckles versus the entire front of the fist, the greater striking force.