Fixes TheAlgorithms#9191: Add module for calculating energy-mass equivalence

Author: Dhruv127

Diff for: physics/einstein_mass_energy_equivalence.py

@@ -0,0 +1,44 @@
+# Calculate Energy from Mass using Einstein's Mass-Energy Equivalence
+
+# This Python script calculates the energy equivalent of a given mass using Albert Einstein's mass-energy equivalence equation, E=mc².
+# The formula E=mc² states that energy (energy_equivalent) is equal to mass (mass_kg) multiplied by the speed of light (speed_of_light_m_per_s) squared.
+
+# Source: https://en.wikipedia.org/wiki/Mass%E2%80%93energy_equivalence
+
+def calculate_energy_from_mass(mass_kg: float, speed_of_light_m_per_s: float = 299792458) -> float:
+    """
+    Calculate the energy equivalent of a given mass using Einstein's mass-energy equivalence equation, E=mc².
+
+    Args:
+        mass_kg (float): Mass in kilograms.
+        speed_of_light_m_per_s (float): Speed of light in meters per second (default value is the speed of light in a vacuum).
+
+    Returns:
+        float: Energy equivalent in joules.
+
+    Examples:
+        >>> calculate_energy_from_mass(1)
+        8.987551787368176e+16
+        >>> calculate_energy_from_mass(5, 3e8)
+        1.125937723421022e+18
+    """
+    # Check if the mass is non-negative
+    if mass_kg < 0:
+        raise ValueError("Mass cannot be negative")
+    
+    # Check if the speed of light is positive
+    if speed_of_light_m_per_s <= 0:
+        raise ValueError("Speed of light must be positive")
+
+    # Calculate energy using the mass-energy equivalence equation
+    energy_equivalent_joules = mass_kg * speed_of_light_m_per_s**2
+    
+    # Return the energy equivalent in joules
+    return energy_equivalent_joules
+
+if __name__ == "__main__":
+    # Import the doctest module to run tests
+    import doctest
+
+    # Run doctests to verify the function's correctness
+    doctest.testmod()