Convert Inch to Bohr Radius
Convert inches to bohr radii instantly. 1 inch = 4.799904e+8 bohr radius — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Bohr Radius to Inch converter for the reverse conversion.
Units explained
Inch
An inch is an Imperial and US customary unit of length defined since 1959 as exactly 25.4 millimeters (0.0254 meters). It is still the standard small unit of length in the United States, the United Kingdom (informally), and a few other countries.
The inch derives from the Roman uncia (one-twelfth of a foot) and survived through Anglo-Saxon and medieval English measurement systems. Various definitions persisted regionally until the 1959 International Yard and Pound Agreement standardized the inch globally as exactly 25.4 mm.
Inches are used in the US and UK for body height, screen sizes (TVs, monitors, phones), tire sizes, plumbing, lumber, paper sizes (US Letter is 8.5 × 11 in), and most consumer product specifications in the United States.
Anglo-Saxon origin (predating 1066); standardized to 25.4 mm exactly by the International Yard and Pound Agreement of 1959, signed by the US, UK, Canada, Australia, New Zealand, and South Africa.
Bohr Radius
The Bohr radius is approximately 5.292×10⁻¹¹ meters — the most probable distance between the proton and electron in a hydrogen atom in its ground state.
Defined by Niels Bohr in his 1913 model of the hydrogen atom. The current CODATA 2018 value of 5.29177210903×10⁻¹¹ m is derived from the elementary charge, electron mass, and Planck's constant.
The Bohr radius is used throughout atomic physics, quantum chemistry, and computational chemistry as the natural length scale for electronic-structure calculations. The atomic unit (a.u.) of length equals the Bohr radius.
Defined by Bohr in 1913; current value via CODATA 2018.
Inch to Bohr Radius conversion formula
The relationship between inches and bohr radii:
To convert inches to bohr radii, multiply the value in inches by 4.799904e+8. To reverse, multiply bohr radii by 2.083375e-9.
How to use this converter
Type a value into the calculator. The result in bohr radii updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Bohr Radius to Inch converter for the reverse direction.
Step-by-step: convert inches to bohr radii
- Write down the value in inches (in).
- Multiply that value by the factor 4.799904e+8.
- The product is the equivalent value in bohr radii (a₀).
- To reverse, multiply the bohr radius value by 2.083375e-9.
Worked examples
Example 1 — Convert 1 in to a₀:
1 × 4.799904e+8 = 4.799904e+8 a₀
Example 2 — Convert 100 in to a₀:
100 × 4.799904e+8 = 4.799904e+10 a₀
Real-world example — Small-scale to atomic-scale
One inch equals 10 million bohr radii — useful for physics curricula that relate everyday measurements to atomic and optical scales.
1 in × 4.799904e+8 = 4.799904e+8 a₀
Real-world example — Centimeter to wavelength scale
One inch equals 10 million bohr radii. Physics curricula use this kind of conversion to relate everyday measurements to atomic and optical scales.
1 in × 4.799904e+8 = 4.799904e+8 a₀
Inch to Bohr Radius conversion table
Standard reference values for converting inches to bohr radii:
| Inch [in] | Bohr Radius [a₀] |
|---|---|
| 0.01 | 4799904.3565494558 |
| 0.1 | 4.799904e+7 |
| 1 | 4.799904e+8 |
| 2 | 9.599809e+8 |
| 3 | 1.439971e+9 |
| 4 | 1.919962e+9 |
| 5 | 2.399952e+9 |
| 10 | 4.799904e+9 |
| 20 | 9.599809e+9 |
| 30 | 1.439971e+10 |
| 40 | 1.919962e+10 |
| 50 | 2.399952e+10 |
| 100 | 4.799904e+10 |
| 500 | 2.399952e+11 |
| 1000 | 4.799904e+11 |
Frequently asked questions
How many bohr radii is 1 inch?
How do I convert inches to bohr radii?
How do I convert bohr radii back to inches?
How many bohr radii is 100 inches?
Popular length unit conversions
Convert Inch to other length units
Show all Inch conversions
Metric / SI (18 units)
Imperial / US Customary (26 units)
Nautical (1 units)
Astronomical (9 units)
Atomic / Physics (6 units)
Typographic (3 units)
Sources & references
Conversion factor (1 in = 4.799904e+8 a₀) verified against the following authoritative sources:
- BIPM — The International System of Units (SI Brochure 9th ed.)
Official BIPM publication defining the seven SI base units (including the meter) and the rules for their use. The global authority on units of measurement.
- NIST — Guide to the SI
US National Institute of Standards and Technology reference covering the SI base and derived units with definitions and usage rules for US technical practice.
- NIST Special Publication 811 — Guide for the Use of the International System of Units
Detailed NIST guide covering exact conversion factors between SI and US customary units along with formatting and rounding conventions.
- NIST — Refinement of values for the yard and pound (Federal Register 1959)
The treaty (signed by US
- International Astronomical Union — System of Astronomical Constants
The IAU defines astronomical units including the AU (149597870700 m exactly) light-year and parsec used in astronomy and astrophysics.