Casio fx-991 CW: Scientific Constants in Calculations
Obtaining the Scientific Constants
I believe we can do this in every mode.
1. Press the [ CATALOG ] button.
2. Scroll to the Sci Constants submenu. It’s faster to scroll up in this case.
3. Press the right button [ → ] to get to the categories.
4. Select the category and press the right button again.
5. Select the constant and press [ OK ].
We can select the back button, the one with the curved arrow, to go back to the previous menu.
I wish the fx-991CW had a custom menu where we could store constants and other commands so we could reduce the number of keystrokes for common constants and commands.
Table of Common Scientific Constants
All scientific constants in the fx-991CW use SI units (meters, kilograms, seconds, Kelvin/Celsius, etc.). I believe the 2018 CODATA values are used, at least with the calculator I bought three years ago in 2022.
Name |
Symbol |
Category |
Value (Norm 1) |
Vacuum Permeability (Magnetic Constant) |
μ₀ |
Universal |
1.256637062 × 10^(-6) N/A² Exact: (4π × 10^(-7)) |
Universal Gravitational Constant |
G |
Universal |
6.6743 × 10^(-11) N m²/kg² |
Vacuum Permittivity (Electric Constant) |
ε₀ |
Universal |
8.854187813 × 10^(-12) F/m |
Speed of Light (in a vacuum) |
c |
Universal |
299,792,458 m/s |
Planck’s Constant |
h |
Universal |
6.62607015 × 10^(-34) J s |
Earth’s Gravity Constant |
gₙ (note the n subscript) |
Adopted Values |
9.80665 m/s² |
Universal Gas Constant |
R |
Physico-Chem |
8.314462618 J/(mol K) |
Avogadro Constant |
Nₐ (the a is capitalized) |
Physico-Chem |
6.02214076 × 10^23 mol⁻¹ |
Boltzmann Constant |
k |
Physico-Chem |
1.380649 × 10^(-23) J/K |
Stefan-Boltzmann Constant (Constant of Proportionality) |
σ |
Physico-Chem |
5.670374419 × 10^(-8) W/(m² K⁴) |
Elementary Charge |
e |
Electromagnetic |
1.602176634 × 10^(-19) C |
Mass of an Electron |
me |
Atomic&Nuclear |
9.109383702 × 10^(-31) kg |
Volume of a Mole at 0° C |
Vm |
Physico-Chem |
0.02271095464 m³/mol |
Atomic Mass Constant (1/12 of mass of a neutral carbon-12 atom) |
m_u (the u is a subscript, classically marked u) |
Physico-Chem |
1.660539067 × 10^(-27) kg |
A full list of the 47 constants can be found here:
Note the manual only lists the symbol.
Examples
Scientific Constants are highlighted in dark blue.
Lorenz Factor
γ = 1 / √(1 – v^2/c^2) (Universal)
γ = time dilation factor
v = 150 × 10^6 m/s, put the entire quantity in parenthesis like this (150×10^6)
γ ≈ 1.154967184
Escape Velocity
v = √(2 * G * m / r) (Universal)
v = velocity required to escape the planet
Radius: r = 7.2 × 10^6 m, again with the ×10^ button, put the entire number in parenthesis (7.2×10^6)
Mass: m = 5.9 × 10^24 kg
v ≈ 10458.69787 m/s
Coulomb’s Law
F = (q1 * q2) / (4 * π * ε₀ * r^2) (Universal)
F = force between two charges
Charge # 1: q1 = 4 × 10^(-5) C
Charge # 2: q2 = 3.3 × 10^(-5) C
Radius: r = 0.24 m (24 cm)
F = 205.9647286 N
Source: Casio fx-1000F/fx-5000F Manual
Solenoid Inductance
L = μ₀ × μr × n^2 × A × h (Universal)
L = inductance in micro henrys (mH)
Relative Permeability: μr = 2.5 (unit-less)
Number of Turns: n = 30/cm
Area: A = 0.2 cm^2
Length: h = 3.5 cm (note the symbol)
L = 0.00197920337 mH
Source: HP 50/49g+/48gII graphing calculator: advanced user’s reference manual
Simple Pendulum
F = -(m * gₙ * x) / l (Adopted Values)
F = force of a pendulum at point x
Position to be analyzed: x = 1 m
Length: l = 1.5 m
Mass: m = 10 lb ≈ 4.535924 kg
F = -29.65481273 N
Source: Casio fx-1000F/fx-5000F Manual
I hope you find this useful, and enjoy the physical constants library of the fx-991CW. Until next time,
Eddie
All original content copyright, © 2011-2025. Edward Shore. Unauthorized use and/or unauthorized distribution for commercial purposes without express and written permission from the author is strictly prohibited. This blog entry may be distributed for noncommercial purposes, provided that full credit is given to the author.
