Mechanics Flashcards
Define: momentum
The product of the mass and velocity of the object.
State: Newton’s Second Law of Motion in terms of momentum
The resultant/net force acting on an object is equal to the rate of change of momentum of the object in the direction of the resultant/net force.
Define: impulse
The product of the resultant/net force acting on an object and the time the resultant/net force acts on the object.
State: The Principle of Conservation of Linear Momentum
The total linear momentum of an isolated system remains constant.
Define: normal force
the force or the component of a force which a surface exerts on an object with which it is in contact, and which is perpendicular to the surface.
Define: A non-conservative force
a force for which the work done in moving an object between two points depends on the path taken. Examples are frictional force, air resistance, tension in a chord, etc.
Define: Inelastic collision
Momentum remains the same. Kinetic energy does not remain the same.
Define: Elastic collision
Momentum remains the same. Kinetic energy remains the same.
State: The principle of conservation of mechanical energy
The total mechanical energy (sum of gravitational potential energy and kinetic energy) in an isolated system remains constant. (A system is isolated when the resultant/net external force acting on the system is zero).
Define: Conservative force
a force for which the work done in moving an object between two points is independent of the path taken. Examples are gravitational force, the elastic force in a spring and electrostatic forces (coulomb forces).
The relationship of Fnet and the change in momentum
Directly proportional
Impulse SI unit
N.s
Momentum SI unit
kg.m.s-1
State: The equation of momentum
p=mv
State: What 2 factors could change the objects momentum?
momentum can change if
1) the object speeds up or slows down
2) the object changes direction
A _____ is required to increase, decrease, or change the direction of momentum
force
State what happens when rebound impacts occur
Velocity and momentum are in the opposite direction if object is collided with another object the momentum then has the opposite sign
State: Partially inelastic collision
Colliding objects move apart and have less kinetic energy after the collision than before.
Define: Isolated system
An isolated system is a physical configuration of particles and or objects that we study
that doesn’t exchange any matter with its surroundings and is not subject to any force
whose source is external to the system.
Define: System
A system is a physical configuration of particles and or objects that we study.
