Read about Physics

Modern Physics for the Layman: the 10 Dimensions.

This video that demonstrates the causes and consequences of the theory of 10 dimensions was released several years ago. However, it is still the best resource on the web for imagining the higher dimensions.

Imagining the Tenth Dimension

Oh, as an Aside: Water balloon not exploding in high-speed (From the 31st of March)

I am so totally stealing this video from Talk Like a Physicist, but it is worth it and I promise I won’t do it again. I really don’t have anything intelligent to add except: COOL!

Calculus Based Physics Formulas: Mechanics

This is just a basic equation list, explanations can be found elsewhere. For the most part derivations are done for you, but it is beneficial to understand how an equation goes from one form to another.

One dimensional Equations of motion (along a single vector direction)
Velocity as a function of time : v_{xf} = v_{xi} + a_x t
Position as a function of time:  x_f = x_i + v_{xi}t + \frac{1}{2}  a_x t^2
Velocity as a function of position: v^2_{xf} = v^2_{xi} + 2a_x ( x_f - x_i)<br />

Projectile Motion
Horizontal motion
Velocity along x: v_{xi} = v_i cos(\theta)
Position from position as a function of time: x_f = v_i cos(\theta)t
Max Horizontal dist: R = v^2_i \frac{sin( 2 \theta_i)}{g}

Vertical Motion
Velocity along y:v_{yi} = v_i sin(\theta)
Position: from position as a function of timey_f = y_i + v_{yi}t - \frac{1}{2} g*t^2
Maximum Height:  h_{max} = v^2_{i} \frac{sin(\theta_i)}{2g}

Circular Motion
Radial Acc: a_r = v^2_r = a cos( \theta)
Tan.

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Units in Physics (mechanical, electricity, magnetism, light and optics) including Si units.

This is a reference list with notes of all SI and derived units in physics. The notes provide a brief explanation of some of the more confusing elements, but be warned that the full explanation could take many pages, and may be explained elsewhere on this website.

Physics has only 5 base units. (Plus the SI units Mole and Candela, but these are rarely used in Physics.)

Name Abbreviation (Symbol) Standard Unit Notes
Name Abbreviation (Symbol) Standard Unit Notes
Length l, x (for distances) Meter (m) A meter is defined as the distance light travels in a vacumm in \frac{1}{299 792 458} of a second (in physics it is customary to use metric measurements although the basic principles apply if you to use feet instead of meters)
Mass m, M (when used with measurements in meters) Kilogram (kg) A kilogram is defined as the weight of a specific platinum-iridium cylinder
Time t Second (s) Seconds are defined as 9,192,631,770 vibrations of radiation from a cesium atom
Temparature T Kelvin (K) A degree kelvin is defined as \frac{1}{273.16} of the distance between absolute 0 and the triple point of water
Electric Current I Ampere (A) An ampere is the amount of charge (C) passing through a surface per second, and is defined as the current which produces a force of 2*10^{-7} newtons per meter of length between two infinitely long, perfectly straight and parallel conductors with an infinitely small cross section separated by one meter in a vacuum..

Each of these base units is defined on fundamental constants, and all other units are based on these five units. At times it useful to break longer equations down to their most basic units to determine if the equation makes sense. The most common combinations of these basic units are given their own symbols and names. These common units are as follows.

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Using the Rules of Physics to Find the Mass of the Planet Crouching Tiger, Hidden Dragon Takes Place on.

The clip that is referenced is near the end of the movie after the two female characters fight at the school, and runs for about 2 -3 minutes.

It doesn’t take any physics experience to realize that “Crouching Tiger Hidden Dragon” is a bad physics movie, however with physics we can show just how bad it really is. The clip I selected runs only a few seconds long but portrays many of the formula’s that one would use in a simple mechanics physics course. Through careful calculations and a little estimation (all double checked) I was able to determine a range of details including the acceleration of gravity on the “planet” this movie takes place in, the diameter of the planet, and the density of the planet. I was also able to determine a few specific examples aside from the acceleration of gravity that show that this movie is a BPM.

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