energy and momentum Flashcards
(12 cards)
define work
energy that a force gives an object when it causes the object to move
Jules J OR N*m
describe positive negative and zero work
Positive: applied force is in the same direction as the objects displacement, the object gains height and or speed, 0-90
Negative: object moves in opposite direction of applied force, 90-180, object slows and or loses height
Zero: directions of displacement is exactly 90, force displacement or angle of cosine is 0
what is energy
ability to do work,
kinetic- motion
potential- position
J
what is the work-energy theorem
when a net force acts on an object, the object accelerates, the force does work on the object and the objects kinetic energy changes
therefore total work done on an object is equal to the change in its kinetic energy
describe potential energy
the stored energy that an object has that can be released into another form
energy stored as result of the vertical position change, relative to reference point
J
describe relationship between potential and kinetic energy
one form often transforms into the other as work is done
NRG is neither created or destroyed, just changes forms
sum of kinetic energy and potential remains constant (Et) in any closed system
explain how non conservative forces affect total mechanical energy
if positive work is done, the object will gain energy
if negative work is done the object will lose energy
what is power
the rate at which work is done
W OR J/s
what is momentum
the quantity of motion that an object has
depends on mass and velocity
Ns or Kgm/s
what is impulse
the change in motion
N*s
the product of that average force and the time exerted
what is newtons third law
for every action there is an equal and opposite reaction
explain the law of Conservation of momentum
in an isolated system, momentum is neither created nor destroyed during any collision
p1=p2
