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Speed of Light Formula:
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The speed of electromagnetic waves in vacuum, commonly denoted as c, is a fundamental physical constant important in many areas of physics. It is the speed at which all electromagnetic radiation propagates in vacuum.
The calculator uses the fundamental formula:
Where:
Explanation: This formula derives from Maxwell's equations and shows the relationship between the speed of light and the electromagnetic properties of vacuum.
Details: The speed of light is a fundamental constant in physics that appears in many physical laws and equations, including Einstein's theory of relativity. It's crucial for understanding electromagnetic phenomena, telecommunications, and cosmology.
Tips: Enter the permeability (μ₀) and permittivity (ε₀) values in their respective units. Standard values are pre-filled: μ₀ = 4π×10⁻⁷ H/m and ε₀ = 8.85×10⁻¹² F/m.
Q1: What is the exact value of the speed of light?
A: The speed of light in vacuum is exactly 299,792,458 meters per second by definition.
Q2: Why is the speed of light constant?
A: According to Einstein's theory of relativity, the speed of light in vacuum is constant and independent of the motion of the source or observer.
Q3: Can anything travel faster than light?
A: According to current physical theories, no information or matter can travel faster than light in vacuum.
Q4: How was the speed of light first measured?
A: Ole Rømer first demonstrated in 1676 that light has a finite speed by observing the timing of Jupiter's moon eclipses.
Q5: Why is the speed of light important in relativity?
A: The constancy of the speed of light is a fundamental postulate of Einstein's theory of relativity and leads to phenomena like time dilation and length contraction.