Science · 6 min
Coulomb's Law — Formula, Units and Worked Examples
Coulomb's law describes the force between electric charges. Learn the formula, the constant k, and a step-by-step numerical example for 2026.
· Redakcja Liczbnik
Blog category · 29 articles
Blog: Science
Science in practice: density, concentrations, Ohm’s law and other formulas with worked examples.
Science · 7 min
Entropy — Basics, Formula and Examples in Physics 2026
What is entropy and how do you calculate it? We explain the second law of thermodynamics, Boltzmann's formula, and entropy using simple physical examples for 2026.
· Redakcja Liczbnik
Science · 6 min
Molar Mass — How to Calculate for Elements and Compounds
Step-by-step guide to calculating molar mass for elements and chemical compounds. Includes the periodic table, worked examples and common mistakes.
· Liczbnik Editorial
Science · 6 min
Ohm's Law Explained — Formula, Examples and Practical Applications
Understand Ohm's Law with clear examples, the V=IR formula and real-world applications in electronics and electrical engineering. Ideal for students.
· Liczbnik Editorial
Science · 7 min
Solution Concentration — Molar, Percentage and Molal Calculations
Learn how to calculate solution concentration: molarity, mass percentage, molality and more. Clear formulas and worked examples for chemistry students.
· Liczbnik Editorial
Science · 6 min
Ohm's Law — How to Calculate Voltage, Current and Resistance
Ohm's law in practice: the formula U = I × R, how to find voltage, current and resistance. Worked numerical example in SI units plus power formulas.
· Redakcja Liczbnik
Science · 6 min
Density — How to Calculate It from the Formula, with Examples
How to calculate the density of a substance: the formula ρ = m / V, SI units, converting kg/m³ to g/cm³, and a step-by-step numerical example.
· Redakcja Liczbnik
Science · 6 min
Molar Concentration — How to Calculate It Step by Step
How to calculate the molar concentration of a solution: the formula c = n / V, finding moles from mass, the unit mol/dm³, and a worked example with salt.
· Redakcja Liczbnik
Science · 6 min
pH of a Solution — How to Calculate It and What It Means
How to calculate the pH of a solution from the hydrogen ion concentration: the formula pH = -log[H⁺], the pH scale, acids and bases, and a worked example.
· Redakcja Liczbnik
Science · 6 min
Kinetic Energy — Formula and Worked Examples
The kinetic energy of a body: the formula Ek = ½mv², the unit joule, the effect of mass and speed, and a step-by-step numerical example in SI units.
· Redakcja Liczbnik
Science · 6 min
Force and Acceleration — Newton's Second Law of Motion
Newton's second law of motion: the formula F = m × a, the unit newton, how to calculate force, mass and acceleration, and a worked example in SI units.
· Redakcja Liczbnik
Science · 6 min
Pressure — How to Calculate It from the Formula p = F / S
How to calculate pressure: the formula p = F / S, the unit pascal, the effect of force and area on pressure, and a step-by-step numerical example in SI.
· Redakcja Liczbnik
Science · 6 min
Average Speed — How to Calculate It from the Formula v = s / t
How to calculate average speed: the formula v = s / t, the units m/s and km/h, unit conversion, and a numerical example with distance and time.
· Redakcja Liczbnik
Science · 6 min
Area and Perimeter of Geometric Figures — Formulas and Examples
Formulas for the area and perimeter of a square, rectangle, triangle and circle. Units, the difference between area and perimeter, and step-by-step examples.
· Redakcja Liczbnik
Science · 6 min
Percentage and Per Mille — How to Calculate Them and How They Differ
How to calculate a percentage and a per mille of a number: the formulas, the difference between percent and per mille, converting fractions, and worked examples.
· Redakcja Liczbnik
Science · 7 min
The Doppler Effect Explained — Formula, Examples and Calculator
What is the Doppler effect, how does the frequency-shift formula work and where is it used? From ambulance sirens to astronomical red-shift and medical ultrasound.
· Redakcja Liczbnik
Science · 7 min
The Doppler Effect - How It Works and How to Calculate It
The Doppler effect is a change in wave frequency observed by a moving receiver or source. Learn the formula, real-life examples, and how to calculate it.
· Redakcja Liczbnik
Science · 7 min
Radioactive Decay - Half-Life and How to Calculate It
What is radioactive decay, how does the law of half-life work, and how do you calculate the remaining amount of a substance after a given time? Formulas, examples, and applications.
· Redakcja Liczbnik
Science · 7 min
Buoyant Force (Archimedes' Principle) - Formula, Examples, and Calculator
The Archimedes buoyant force determines whether an object sinks or floats. Learn the formula F = ρ x g x V, Archimedes' principle, and its applications in engineering and medicine.
· Redakcja Liczbnik
Science · 7 min
How to Calculate the Area of a Triangle - Formulas and Examples
The area of a triangle can be calculated in several ways. Learn the base times height formula, Heron's formula, and the side-and-angle method, with step-by-step examples.
· Redakcja Liczbnik
Science · 6 min
How to Calculate the Volume of a Cylinder - Formula and Examples
The volume of a cylinder is calculated as pi times radius squared times height. Learn the formulas for volume and surface area, and how to convert the result to liters.
· Redakcja Liczbnik
Science · 8 min
Ideal Gas Law Calculator — PV=nRT Formula and Examples
Master the ideal gas law PV=nRT with a step-by-step calculator guide. Includes formula derivations, unit conversions, real gas corrections, and solved chemistry problems.
· Liczbnik Editorial
Science · 7 min
How to Calculate a Logarithm — Formulas and Calculator 2026
Logarithms step by step: definition, formulas, properties and worked examples. Learn how to calculate log, ln and log2 without mistakes.
· Redakcja Liczbnik
Science · 7 min
Trigonometry: Sin, Cos, Tan — Formulas and Online Calculator
Learn the trigonometric functions sin, cos, tan and cot — definitions, formulas, values for common angles, and applications in geometry and physics.
· Redakcja Liczbnik
Science · 7 min
Areas and Volumes of Geometric Solids — Formulas and Calculator
A complete set of formulas for surface area and volume of solids: cube, cylinder, cone, sphere, prism and more — with worked examples.
· Redakcja Liczbnik
Science · 7 min
Volume Converter — Liters, Gallons, m³, Milliliters Online
How do you convert volume between liters, gallons, m³, milliliters and ounces? Formulas, conversion tables and an online calculator for every unit.
· Redakcja Liczbnik
Science · 7 min
The Ideal Gas Law (PV=nRT) — How to Calculate It and Applications
The ideal gas law PV=nRT step by step: what the variables mean, how to calculate pressure, volume and temperature, and examples of applications in physics.
· Redakcja Liczbnik
Science · 5 min
Temperature Conversion: Celsius, Fahrenheit and Kelvin Explained
How to convert between Celsius, Fahrenheit and Kelvin temperature scales: formulas, comparison tables and practical everyday examples.
· Liczbnik Editorial
Science · 5 min
Energy Unit Converter: kWh, MJ, kcal — How to Compare Them
How to convert kilowatt-hours, megajoules, and kilocalories? Conversion formulas and practical examples from energy bills and nutrition labels.
· Liczbnik Editorial