CONCEPTS -- LINEAR MOTION

Velocity --» distance an object moves over a specific time in a specific direction.

• Formula: v = d/t where v = velocity, d = distance, & t = time.

• Average Velocity --» Velocity measure using two points of reference and total time between those points.

• Instantaneous Velocity --» The velocity of an object at a specific point in its travel.

Acceleration --» An object's change in velocity.

• Formula: a = v2 - v1/t where a = acceleration, v2 = final velocity, v1 = initial velocity, & t = time.

Momentum --» The quantity of motion an object possesses. The greater this quantity the greater the resistance to the change in direction and velocity.

• Formula:: p = (m)(v) where p = momentum, m = mass of object, & v = velocity of object..

Conservation of Momentum --» Also considered as momentum transfer.

• For isolated systems the total momentum of both systems will remain the same. Depending on the interaction of objects one may reduce momentum but the other will gain momentum.
  

Impulse --» Is a change in the momentum of an object. This change can be either be slowing down or speeding up an object of mass.

• Formula: Imp or J = p₂ - p₁  where Imp = Impulse, F = force, t = time, p₂ = final momentum, and p₁ = initial momentum.
  • Another way of looking at this formula is (F)(t) = p₂ - p₁ = (Force applied)(time the force is applied) = Impulse (a change in momentum)

• Possible Formulations of Momentum Variables:

  • Change in Momentum = (less force)(longer time)

  • Change in Momentum = (less force)(shorter time) 

  • Change in Momentum = (more force)(shorter time) 

  • Change in Momentum =  (more force)(longer time)
     
• Technique Implications

  • Shock Absorption technique uses application of (small force) over (extended time).

  • Abrupt Directional Changes use application of (larger force) over (shorter time).

  • Acceleration of an Object use application of (larger force) over (extended time)