Energy & Classification Of Collisions Flashcards
Relative Velocity
Vector difference between velocity of two bodies
With colliding carts, in most cases, there is no change in relative velocity because velocity magnitude is the same before and after collision.
Relative Speed
Magnitude of relative velocity
Elastic Collision
Collision in which relative speed before collision is the same as relative speed after collision.
E.g Ball Bouncing off Hard Floor
Kinetic Energy & Momentum during Elastic Collision
Both the momentum and kinetic energy are conserved.
Inelastic Collision
A collision in which relative speed is not conserved.
E.g Tennis Ball to Floor
Kinetic Energy & Momentum during Inelastic Collision
Momentum is conserved but kinetic energy is not.
Totally Inelastic Collision
Collision in which two objects move together after collision so their relative speed is zero.
E.g Dropping dough ball to the floor
Kinetic Energy & Momentum during Totally Inelastic Collision
The momentum is conserved, kinetic energy is lost and converted to other forms of energy (internal)
Kinetic Energy
Observable energy of motion of an object
Kinetic Energy Equation
K = 1/2mv^2
K = 1/2(m1 + m2)v^2
State
Every physical variable of an object: Shape, temperature, etc.
Process
Transformation of a system from initial state to final state.
E.g Collision changing motion of state of objects; ice melting
Irreversible Changes
Changes that occur in state of colliding objects that cannot undo themselves
This occurs in ALL Inelastic Collision.
Reversible Change
No permanent changes in state of colliding objects
This occurs in elastic collisions.
Internal Energy
Quantity of energy having same units as Kinetic Energy within state of object.
An increase in internal energy decreases kinetic energy as one form of energy is converted to another form of energy. The sum of the energy system does not change.
