Difference between revisions of "Physics Lectures"
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The tendency for an object to continue moving the way it is moving. This is a '''''vector''''' quantity. | The tendency for an object to continue moving the way it is moving. This is a '''''vector''''' quantity. | ||
Momentum is ''always'' conserved in collisions | Momentum is ''always'' conserved in collisions | ||
+ | '''m1v1+m2v2=m1v(f1)+m2v(f2)''' | ||
+ | Totally elastic collisions → kinetic energy is conserved | ||
+ | '''m1v1+m2v2=m1v(f1)+m2v(f2)''' | ||
+ | Inelastic collisions → | ||
+ | ---- | ||
+ | ====Electricity==== | ||
+ | The flow of electric charge, particularly electrons, to power circuits and components. | ||
+ | Conductors allow charge to flow. Insulators prevent the flow of charge. |
Revision as of 20:34, 20 December 2016
Matt, I'm just throwing in all of the notes, we can simplify this later on
Contents
Physics Lecture
Vectors
Plenty of measurements in physics require both magnitude and direction to be accounted for. These are called vectors, and are represented as arrows.
Motion
Changes in an object's location or position over a period of time. Several measurements in motion are vectors:
- Displacement (from starting to destination point)
- d=vt
- Distance can be measured in feet or meters
- Velocity (speed with direction)
- v=d/t
- Velocity can be measure in ft/s or m/s
- Acceleration (how quickly does the velocity change?)
- a=v/t
- Acceleration can be measured in ft/s^2 or m/s^2
- There are a few types of motion
- Linear (1D, straight line)
- Parabolic (2D, including gravity)
- Rotational (turning around an axis)
- Circular (revolution, not rotation)
- Periodic (oscillations, back-and-forth)
Forces
A mass of any kind requires an unbalanced force in order to change its motion(accelerate)
Forces are vectors that result in the motion of objects when they are unbalanced
Newton's Three Laws of Motion:
- Inertia: objects will remain in motion or at rest unless an unbalanced force acts on it.
- F=ma
- For every action, there is an equal and opposite reaction
Inertia is not a force. It is the natural tendency for objects to continue what they are doing
- Forces
- Applied (direct propulsion or contact)
- Tension (pulled)
- Friction (resistance)
- Normal (surface)
- Weight (gravity)
The force of friction depends on the surfaces in contact with each other. Friction always opposes potential or occurring motion.
Simple Machines
A machine to make a task easier to perform(?)
- Lever: Inclined plane.
- Wedge
- Screw
- Pulley: Wheel and Axle
- W=F*d
- If an object is displaced by some force, when the work is accomplished. This is a vector measured in Joules
Power
P=W/t=F*V
Energy
A requirement in order to accomplish work (Joules)
- Mechanical (kinetic and potential)
- Nuclear
- Thermal (friction)
- Chemical
K=1/2mv^2
Momentum
p=mv The tendency for an object to continue moving the way it is moving. This is a vector quantity. Momentum is always conserved in collisions m1v1+m2v2=m1v(f1)+m2v(f2) Totally elastic collisions → kinetic energy is conserved m1v1+m2v2=m1v(f1)+m2v(f2) Inelastic collisions →
Electricity
The flow of electric charge, particularly electrons, to power circuits and components. Conductors allow charge to flow. Insulators prevent the flow of charge.