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Rest Energy Calculator

1. What is the Rest Energy Calculator?

Definition: This calculator computes the rest energy (\( E_0 \)) of an object based on its mass (\( m \)), using Einstein's famous equation.

Purpose: It is used in physics to determine the energy equivalent of an object's mass at rest, applicable in nuclear physics, particle physics, and theoretical studies of mass-energy equivalence.

2. How Does the Calculator Work?

The calculator uses the relationship:

\[ E_0 = m c^2 \]

Where:

  • \( E_0 \) — Rest energy (in various units)
  • \( m \) — Mass of the object
  • \( c \) — Speed of light (\( 299,792,458 \, \text{m/s} \))

Explanation: Enter the mass of the object in the chosen units, and the calculator computes the rest energy using the speed of light (\( c \)). Results are displayed with 5 decimal places, using scientific notation if the value exceeds 100,000. For the default input (\( m = 1 \, \text{kg} \)), the calculated rest energy \( E_0 \) is approximately 8.98755e+16 Joules.

3. Importance of Rest Energy

Details: Rest energy represents the energy inherent in an object's mass, as described by Einstein's theory of relativity. It is fundamental in understanding nuclear reactions, where mass is converted into energy, and in theoretical physics for studying mass-energy equivalence.

4. Using the Calculator

Tips: Enter a positive value for mass with up to 4 decimal places (step of 0.0001), then click "Calculate." Results show the rest energy \( E_0 \) in Joules, Kilojoules, and Electronvolts. Values greater than 100,000 are displayed in scientific notation with 5 decimal places. Note that the speed of light (\( c \)) is a constant (\( 299,792,458 \, \text{m/s} \)).

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