Author: kegasa
●Everyone's DIY Math / General Math
●Everyone's DIY Projects (Science) / Physics (General)
Isothermal compression and isothermal expansion, using 1 cubic meter of nitrogen at 0°C and 1 atmosphere as the referenceadiabatic process
What happens if you fill a 1-meter-square cube with nitrogen at 1 atmosphere of pressure and compress it with a weight?adiabatic process
Schwarzschild radiusSchwarzschild radius
●Everyone's DIY Projects (Science) / Physics (Sound and Light)
Snell's and Fresnel's Formulas (Fresnel) TableThe reflectance of light incident on the surface of glass from the air at an angle of incidence s1
Snell's and Fresnel's laws (Fresnel) graphThe reflectance of light incident on the surface of glass from the air at an angle of incidence s1
Formula for Calculating Wavelength from LED VoltageFormula for Calculating Wavelength from LED Voltage
Formula for calculating voltage from the wavelength of an LEDFormula for calculating voltage from the wavelength of an LED
Diopter, Focal Length, and Magnification in EyeglassesEyeglass lens prescription: diopter = dpt = D = SPH Lens focal length: focus mm Lens magnification: Magnification relative to the minimum focal length of 250 mm (0.25 m) for an adult with uncorrected vision
Calculating the radius of curvature and thickness of a lens based on its focal length and refractive indexGiven a lens with a diameter D, a refractive index N, and a focal length f, where the radii of curvature R on both surfaces are equal, determine the radius of curvature R and the central thickness t for a convex lens, or the radius of curvature R and the peripheral thickness for a concave lens.
Calculate the focal length, radius of curvature, and thickness of a lens based on the prescription strength and refractive indexGiven a lens with a diameter D, a refractive index N, and a power of SPH, where the radii of curvature R on both surfaces are equal, determine the focal length f and: the radius of curvature R and central thickness t of a convex lens, or the radius of curvature R and peripheral thickness of a concave lens.
Calculate the image distance based on the lens focal length and the distance from the objectCalculate the distance to the image using the focal length f and the distance a to the object
Calculate the image distance and magnification based on the lens focal length and the distance from the objectCalculate the distance to the image using the focal length f and the distance a to the object
●Everyone's DIY Projects (Science) / Physics (Electromagnetism)
Table of Nagaoka Coefficients (R = Coil Radius, L = Coil Length)k = 1/sqrt(1 + (L/(2*R))^2) k2 = k^2 Kn = (4/(3*pi*sqrt(1-k2)) * (((1-k2)/k2) * ellipticK(k) - ((1-2*k2)/k2) * ellipticE(k) - k))
Peak wavelength of blackbody radiation (Wien's displacement law)Wien's displacement law
The capacitance of a sphere of radius rthe self-capacitance of a conducting sphere of radius R
Received signal strengthAttenuation of Radio Waves in Free Space
Calculating the surface temperature of Earth without the greenhouse effect using Hansen's equationAssuming the Earth’s thermal conductivity is infinite and its thermal resistance is zero, the equation explained by Hansen, based on solar radiation and blackbody radiation, shows that without greenhouse gases, the Earth’s surface temperature would drop to -18°C. Science, August 23, 1981 issue Te = [So(1 - A)/4σ]^(1/4)
Calculating the surface temperature of a regular tetrahedron using Hansen's formula from NASAAssuming the Earth’s thermal conductivity is infinite and its thermal resistance is zero, the equation explained by Hansen, based on solar radiation and blackbody radiation, shows that without greenhouse gases, the Earth’s surface temperature would drop to -18°C. Science, August 23, 1981 issue Te = [So(1 - A)/4σ]^(1/4)
Calculating the surface temperature of a sphere using Hansen's formula from NASAAssuming the Earth’s thermal conductivity is infinite and its thermal resistance is zero, the equation explained by Hansen, based on solar radiation and blackbody radiation, shows that without greenhouse gases, the Earth’s surface temperature would drop to -18°C. Science, August 23, 1981 issue Te = [So(1 - A)/4σ]^(1/4)
Field Strength ConversionPower density, electric field, magnetic field, and magnetic flux density at a vacuum impedance of 120π = 377 Ω
●Everyone's DIY Projects (Science) / Chemistry (General)
Quadratic Equations: Needs correction!Quadratic Equations Formula for Solutions (Full Version)—Simplified by substituting parts of the equation I used the formula from Wikipedia, but the result differs slightly from the value given in the formula.
Calculate the pH of rainwater (freshwater) (carbon dioxide is in equilibrium between the atmosphere and rainwater)Calculate the hydrogen ion concentration, pH, and total dissolved carbon dioxide (DIC) in rainwater (freshwater)
Determine the pH of seawaterGiven the partial pressure of carbon dioxide (pCO₂) and the dissolved inorganic carbon (DIC) concentration in the atmosphere, calculate the pH of seawater.
The proportion of each carbonic acid component relative to the total carbonic acid at dissociation equilibrium (determines the pH)The proportion of each carbonate component in total dissolved carbonates in water: [DIC] = a [H₂CO₃], [DIC] = b [HCO₃⁻], [DIC] = c [CO₃²⁻]
Table showing the proportion of each carbonate component relative to total carbonates in waterThe proportion of each carbonic acid component relative to total carbonic acid at dissociation equilibrium (determines pH) The proportion of each carbonic acid component relative to total carbonic acid in water
Graph showing the proportion of each carbonate component in total carbonates in waterThe proportion of each carbonic acid component relative to total carbonic acid at dissociation equilibrium (determines pH) The proportion of each carbonic acid component relative to total carbonic acid in water
Calculating the pH of sodium bicarbonate (baking soda) using a quartic equationQuartic Equation Function Calculating the pH of Sodium Bicarbonate (Baking Soda) Using a Quartic Equation Practical pH Calculations (Amphoteric Electrolytes)
Plotting the pH of sodium bicarbonate (baking soda) using a quartic equationPractical pH Calculations (Amphoteric Electrolytes) – Quartic Equation Function
Calculating the pH of sodium bicarbonate (baking soda) using a quartic equation, including pCO₂Quartic Equation Function Calculating the pH of Sodium Bicarbonate (Baking Soda) Using a Quartic Equation Practical pH Calculations (Amphoteric Electrolytes)
Calculate the pH of rainwater (freshwater) (carbon dioxide is in equilibrium with the atmosphere) at 25°CCalculate the hydrogen ion concentration, pH, and total dissolved carbon dioxide (DIC) in rainwater (freshwater) Calculations based on a water temperature of 25°C
Calculating the pH of sodium bicarbonate (baking soda) using a fourth-degree equation at 25°CQuartic Equation Function Calculating the pH of Sodium Bicarbonate (Baking Soda) Using a Quartic Equation Practical pH Calculations (Amphoteric Electrolytes)
Calculating the pH of sodium bicarbonate (baking soda) using a quartic equation at 40°CQuartic Equation Function Calculating the pH of Sodium Bicarbonate (Baking Soda) Using a Quartic Equation Practical pH Calculations (Amphoteric Electrolytes)
Calculate the pH of rainwater (freshwater) (carbon dioxide is in equilibrium with the atmosphere) at 5°CCalculate the hydrogen ion concentration, pH, and total dissolved carbon dioxide (DIC) in rainwater (freshwater) Calculations based on a water temperature of 5°C
Calculate the pH of rainwater (freshwater) (carbon dioxide is in equilibrium with the atmosphere) at 40°CCalculate the hydrogen ion concentration, pH, and total dissolved carbon dioxide (DIC) in rainwater (freshwater) Calculations based on a water temperature of 5°C
Calculating the pH of sodium bicarbonate using a quartic equation, with pCO₂ at 40°CQuartic Equation Function Calculating the pH of Sodium Bicarbonate (Baking Soda) Using a Quartic Equation Practical pH Calculations (Amphoteric Electrolytes)
●Everyone's DIY Projects (Science) / Astronomy
●Everyone's DIY Projects (Science) / Weather
●Everyone's DIY Projects (Practical Skills) / Electricity & Circuits
Inductance of a cylindrical coil (R = radius, L = length, N = number of turns)Inductance of a circular loop antenna (radius R, length L) S = πR²; Lcoil = Kn * ur * μ₀ * S * N² / L * 10⁶;
The Nagaoka coefficient Ks and inductance L of a square loop antennasquare loop antenna (side a = p, side b = p) L Rr Rac η
The Skin Effect and the Resistance of Circular Copper WireSkin depth of copper and resistance of round wire
Inductance of a single-turn circular loop coilSelf-inductance of a thin wire Circular loop
Inductance of a rectangular coil (b × d)Self-inductance of a rectangle made of round wire
Short wire antenna h Ra Xc ηShort Vertical Antenna height, diameter Ra radiation
Aluminum Wire: Diameter, Length, Weight, Resistance, and AC Resistance (Skin Effect)Aluminum Wire Length and Diameter for Rdc Rac Weight
Cylindrical coil μH (R = radius, L = length, N = number of turns) CD50Inductance of a circular loop antenna (radius R, length L) S = πR²; Lcoil = Kn * ur * μ₀ * S * N² / L * 10⁶;
LC resonant circuitLC resonant circuit to measure capacitance
Magnetic susceptibility of a rotating ellipsoidDemagnetizing factor of an ellipsoid
Magnetic susceptibility of an ellipsoidDemagnetizing factor of an ellipsoid
Equivalent Impedance of an LC Parallel Resonant CircuitEquivalent Impedance of an LC Parallel Resonant Circuit
Gain of a Dipole AntennaGain of a dipole antenna
Calculate power density and electric field strength from transmit power and antenna gainAntenna Gain, Transmit Power, Distance to E, H, B
Equivalent impedance of an LC parallel resonant circuit (μH)Equivalent Impedance of an LC Parallel Resonant Circuit
Gain and Matching Coil for a Wire Antenna with a Wavelength < 0.1λ at 828 kHzShort Vertical Antenna height, diameter Ra radiation
Equivalent impedance of an LC parallel resonant circuit at 828 kHzEquivalent Impedance of an LC Parallel Resonant Circuit
Gain and Matching Coil for Wire Antennas with a Wavelength of 0.1λ or Less at 60 kHzShort Vertical Antenna height, diameter Ra radiation
Determining the Resonance Frequency of an LC ResonatorResonant frequency of an LC resonator
Impedance Converter (Matching Circuit)Impedance Matching Z1:Z2 (R1:R2) Z1 > Z2 Z1 to Z2 matching using series R1 and parallel R2
Calculation of the Nagaoka Coefficient (R = coil radius, L = coil length) in metersk = 1/sqrt(1 + (L/(2*R))^2) k2 = k^2 Kn = (4/(3*pi*sqrt(1-k2)) * (((1-k2)/k2) * ellipticK(k) - ((1-2*k2)/k2) * ellipticE(k) - k))
Impedance Matching NetworkImpedance Matching Network Rs in series, Ls in parallel, Cp, Rp
Converting E96-series notation for surface-mount chip resistors to resistance valuesSMD Resistance Value Code\ E96 Series
The original method for calculating power density and electric field strength from transmit power and antenna gainAntenna Gain, Transmit Power, Distance to E, H, B
Power Loss in Top-Runner Transformers Rated at 500 kVA or LessLosses in Top Runner transformers rated at 500 kVA or less.