Mile per hour to Speed of light Conversion Calculator: Free Online Tool
Convert miles per hour to speed of light with our free online speed converter.
Mile per hour to Speed of light Calculator
How to Use the Calculator:
- Enter the value you want to convert in the 'From' field (Mile per hour).
- The converted value in Speed of light will appear automatically in the 'To' field.
- Use the dropdown menus to select different units within the Speed category.
- Click the swap button (⇌) to reverse the conversion direction.
How to Convert Mile per hour to Speed of light
Converting Mile per hour to Speed of light involves multiplying the value by a specific conversion factor, as shown in the formula below.
Formula:
1 Mile per hour = 1.4912e-9 speed of lightExample Calculation:
Convert 60 miles per hour: 60 × 1.4912e-9 = 8.9470e-8 speed of light
Disclaimer: For Reference Only
These conversion results are provided for informational purposes only. While we strive for accuracy, we make no guarantees regarding the precision of these results, especially for conversions involving extremely large or small numbers which may be subject to the inherent limitations of standard computer floating-point arithmetic.
Not for professional use. Results should be verified before use in any critical application. View our Terms of Service for more information.
What is a Mile per hour and a Speed of light?
Miles per hour (mph, MPH, or mi/h) is an imperial and US customary unit of speed expressing the number of statute miles traveled in one hour.
The speed of light in vacuum, commonly denoted by 'c', is a universal physical constant important in many areas of physics. Its exact value is defined as 299,792,458 meters per second.
Note: The Mile per hour is part of the imperial/US customary system, primarily used in the US, UK, and Canada for everyday measurements. The Speed of light belongs to the imperial/US customary system.
History of the Mile per hour and Speed of light
Miles per hour became prominent with the rise of automotive transportation in countries using the imperial system, particularly the United Kingdom and the United States. It provided a practical measure for road travel speeds and regulations.
The concept that light travels at a finite speed has been explored since antiquity. Early quantitative estimates were made by Ole Rømer in 1676. Increasingly accurate measurements were made over centuries, culminating in the 1983 definition by the General Conference on Weights and Measures, which fixed the speed of light to its current value, thereby defining the meter based on 'c' and the second.
Common Uses for miles per hour and speed of light
Explore the typical applications for both Mile per hour (imperial/US) and Speed of light (imperial/US) to understand their common contexts.
Common Uses for miles per hour
- Road Traffic (US/UK): The standard unit for speed limits and vehicle speeds (speedometers) in the United States, United Kingdom, and a few other countries.
- Rail Transport (US/UK): Often used for train speeds in these same countries.
- Meteorology (Informal): Sometimes used informally in the US/UK for wind speed in public weather reports, though knots or m/s are preferred in official meteorological contexts.
- Sports: Used in some sports like baseball (pitch speed) and sometimes informally in running or cycling in relevant countries.
Common Uses for speed of light
- Physics: Fundamental constant in Einstein's theory of relativity (E=mc²), electromagnetism, and cosmology.
- Astronomy: Measuring vast cosmic distances (light-years).
- Telecommunications: Determining signal propagation speed in fiber optics and wireless communication.
- GPS: Accurate timing based on signal travel time from satellites.
Frequently Asked Questions
Questions About Mile per hour (mph)
Which countries use mph for speed limits?
Miles per hour is primarily used for road speed limits in the United States, the United Kingdom, and some Caribbean nations.
Is mph an SI unit?
No, mph is part of the imperial and US customary systems. The SI unit for speed is meters per second (m/s).
How do you convert mph to km/h?
Multiply the speed in mph by 1.60934. So, 60 mph is approximately 96.6 km/h.
How do you convert mph to ft/s?
Multiply the speed in mph by 1.46667. So, 60 mph is approximately 88 ft/s.
About Speed of light (c)
Is the speed of light always the same?
The speed of light in vacuum (c) is constant and independent of the observer's motion or the source's motion. However, light travels slower when passing through materials like water or glass. The ratio by which it slows down is the material's refractive index.
Can anything travel faster than the speed of light?
According to the theory of special relativity, no object with mass can be accelerated to the speed of light, and no information can travel faster than 'c' in a vacuum.
How is the speed of light related to the meter?
Since 1983, the meter is defined as the distance light travels in vacuum during a time interval of 1/299,792,458 of a second. This definition fixes the speed of light exactly.
Conversion Table: Mile per hour to Speed of light
| Mile per hour (mph) | Speed of light (c) |
|---|---|
| 1 | 0 |
| 5 | 0 |
| 10 | 0 |
| 25 | 0 |
| 50 | 0 |
| 100 | 0 |
| 500 | 0 |
| 1,000 | 0 |
All Speed Conversions
Conversion Formula
1 mph = 1.491165e-9 c
Where 1 Mile per hour (mph) equals the calculated value in speed of light (c).