Overview
1 in = 2.54 cm
Measuring angles clockwise makes them negative angles!
Underline of a zero in a number indicates the last significant digit counted.
.5 rounds down!. .5## where numbers are not 0 round up!.
Midpoint Rounding
Classical Physics
- Mechanics
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- Study of motion Kinematics
- Description of motion
- Dynamics
- Causes of motion
- Thermodynamics
- Study of heat and work
- Electricity & Magnetism
- ?
- Relativity
- Very fast
- Quantum Mechanics
- Very small
Units
7 Fundamental Units
SI Units
- Time
- Second
- Length
- Meter
- Mass
- ?
- Temp
- ?
- Current
- ?
- Luminous Intensity
- ?
- Quantity
- ?
Derived Units
- Derived Units
- Combinations of SI Units
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Speed = m/s
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Momentum = kg m/s
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Volume = m^3
Unit Conversions
15cm to in -> 15cm (1in/2.54cm), centimeters cancel = 5.9 in.
You always have more of the smaller unit. Little unit number should always be larger.
Prefixed Units
| Prefix | Symbol | Scientific Notation | Power of 10 |
|---|---|---|---|
| giga | G | 10^9 | 9 |
| mega | M | 10^6 | 6 |
| kilo | k | 10^3 | 3 |
| centi | c | 10^-2 | -2 |
| milli | m | 10^-3 | -3 |
| micro | u | 10^-6 | -6 |
| nano | n | 10^-9 | -9 |
One-Dimensional Motion
Requires position & time. Both of these are kinematic variables.
- Motion
- A change in position over time.
- Time Interval second
- Change in time.
Δtort2 - t1orfinal - initial- Displacement meters
- A directional unit.
- The change in position.
Δxorx2 - x1orfinal - initial- Positive went right, negative went left.
- Velocity meters/second
- A directional unit.
- Displacement per second.
- Positive moves right, negative moves left.
Δx/Δt- Speed meters/second
- Speed = total distance / Δt
- Total distance covered per second over an interval.
- Does not have a direction, speed is always positive.
- Acceleration meters/second/second
- acceleration = Δv / Δt
- A directional unit, may be positive or negative.
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- A positive acceleration does not guarantee that you are speeding up.
- Change in velocity per second
- When an object accelerates it either speeds up or slows down depending on the direction of motion and signs.
- Every second you add the acceleration onto the velocity.
Δ gives us average values, finite intervals. dt gives us instantaneous values of on artibrarily small time interval, differential intervals.
Intervals
lim(Δt->0) [Δx/Δt] = [dx/dt]