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## Ignore words

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mechanics
branch of applied mathematics dealing with motion and the forces producing motion
Dynamics
A branch of physics that focuses on force and how they relate to motion.
kinematics
branch of mechanics that explains the "what" and "how" of motion
Mechanical Energy
The energy an object has because of its motion or position.
momentum
(p) vector quantity describing the quantity of motion or inertia in motion. Recognizes that both mass and velocity have a part in the motion of an object and is proportional to both (is zero …
impulse
a large change in momentum over a short period of time
Impulse momentum theorem
related to Newton's second law, a = velocity / time = Net Force / mass, larger time intervals require smaller amounts of force and vice versa (i.e. seat belt and air bag reasoning) (delta p = Impulse)
conservation
amount never changes within a closed and isolated system
Closed System
A system containing a fixed amount of matter; it can still exchange energy with the surroundings.
Isolated System
A system that has are no energy transfers between that system and its surroundings.
elastic interaction
collisions in which colliding objects rebound without a lasting change in shape or sound or heart generation
inelastic interaction
a collision in which the colliding objects become tangled or coupled together, distorted (shape changes) and/or generate heat or sound during the collision
explosive interaction
an interaction in which the objects of the system are initially at rest before the parts interact and fly apart because of the release of energy stored within the system
acceleration
(physics) a rate of change of velocity
Energy
(physics) the capacity of a physical system to do work
external force
a force applied to a system from outside the system, the most common of which are weight, support or normal force, friction, and fluid resistance
force
(interactions between two objects)
Interaction
A mutual action between objects where each object exerts an equal and opposite force on the other
internal forces
a force applied between components within the system. Cannot cause the momentum of a system as a whole to change
Law of Conservation of Momentum
If no external forces act on a system, then the total momentum of that system remains the same
net momentum
the sum of the individual momenta of each object within the system
system
A collection of components organized to accomplish a specific function or set of functions.
Velocity
a speed in a particular direction.
yes
Will it be stronger wind if there is a fast flow in pressure?
Yes - twice that of A or B
If you catch the ball and then immediately throw it back (again, on the skateboard), do you experience an impulse?
Yes, but in opposite directions that cancel
If you start to throw the ball, but do not let go, do you experience an impulse?
T/F The forces of impact on a bug and a car windshield are the same magnitude
True (the forces of the bug and the windshield cancel, leaving the bug stationary on the windshield)
True (time interval = time interval)
T/F The duration of the impact of the bug on the windshield is the same as the duration of the impact of the windshield on the bug
True (Net force * time interval = Net Force * time interval)
The impulses on the bug and on the car windshield are the same magnitude
The changes in speed of the bug and of the car windshield are the same
False (car has greater mass, so less change in velocity, bug has greater change in velocity, so less mass)
Area under the graph
What does the impulse equal on a force-time graph?
change in momentum equation
(delta)p = m(vA - vB)
impulse equation
Impulse = F(time interval)
conservation of momentum equation
p(net of system, before interaction) = p(net of system, after interaction)
(mBvB) after
conservation of momentum in an elastic interaction equation
(mAvA)before + (mBvB)before = (mA + mB)vafter
conservation of momentum in an inelastic interaction equation
0 = (mAvA)after + (mBvB)after
Conservation of momentum in an explosive interaction, objects initially at rest
P=
mass x velocity or mv
rate of change of momentum=
the net force applied to it; ∑F= ∆p/∆t
kinetic energy, momentum
What is conserved in an elastic collision?
kinetic energy
a running dog
Ballistic Pendulum
Conservation of energy to calculate height