Understanding E=mc²: The Mass-Energy Equivalence
Albert Einstein's equation, E=mc², is arguably the most famous formula in all of physics. It expresses a profound connection between mass and energy, known as mass-energy equivalence. This principle states that mass is a concentrated form of energy and that the two can be converted into one another.
What the Formula Means
The formula can be broken down into three parts:
- Erepresents Energy, measured in Joules (J). It is the total energy of an object at rest.
- mrepresents Mass, measured in kilograms (kg). This is the "rest mass" of the object.
- crepresents the Speed of Lightin a vacuum, a universal constant approximately equal to 299,792,458 meters per second.
The equation shows that the energy (E) contained within a certain amount of mass (m) is equal to that mass multiplied by the speed of light squared (c²). Because the speed of light is such an enormous number, this formula reveals that even a tiny amount of mass can be converted into a tremendous amount of energy.
Worked Example
Let's calculate the energy contained in 1 kilogram of mass:
- Given Mass (m):1 kg
- Speed of Light (c):299,792,458 m/s
- Formula:$$E=mc^2$$
- Calculation:$$E=1 \text{ kg} \times (299,792,458 \text{ m/s})^2$$
- Result:$$E \approx 8.988 \times 10^{16} \text{ Joules}$$
This massive amount of energy is what powers nuclear reactions and the stars themselves.
How to Use This Calculator
This tool can solve for either energy or mass. The speed of light (c) is a constant and is provided for reference.
- To find Energy (E):Enter a value for Mass (m) and select its unit. The equivalent energy will be calculated instantly.
- To find Mass (m):Enter a value for Energy (E) and select its unit. The equivalent mass will be calculated instantly.
- You can change the units for any field, and the other values will update in real-time.
- Click the "Clear" button to reset the calculator.
