Convert Atomic Mass Unit to Dram (avoirdupois)
Convert atomic mass unit to drams (avoirdupois) instantly. 1 atomic mass unit = 9.371813e-25 dram (avoirdupois) — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Dram (avoirdupois) to Atomic Mass Unit converter for the reverse conversion.
Units explained
Atomic Mass Unit
One unified atomic mass unit (u) is defined as 1/12 the mass of a carbon-12 atom, about 1.6605E-27 kg.
Introduced to give atomic and molecular masses convenient numerical values.
Atomic, molecular, and nuclear physics and chemistry.
The unified (carbon-12) scale was adopted by IUPAC and IUPAP in 1960-1961.
Dram (avoirdupois)
The avoirdupois dram (dr) equals one-sixteenth of an ounce, about 1.77 grams.
From Greek 'drachma' through Latin 'dragma'.
Historically pharmacy; today occasional cooking and firearms (powder) use.
Defined as 1/256 of the avoirdupois pound.
Atomic Mass Unit to Dram (avoirdupois) conversion formula
The relationship between atomic mass unit and drams (avoirdupois):
To convert atomic mass unit to drams (avoirdupois), multiply the value in atomic mass unit by 9.371813e-25. To reverse, multiply drams (avoirdupois) by 1.067029e+24.
How to use this converter
Type a value into the calculator. The result in drams (avoirdupois) updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Dram (avoirdupois) to Atomic Mass Unit converter for the reverse direction.
Step-by-step: convert atomic mass unit to drams (avoirdupois)
- Write down the value in atomic mass unit (u).
- Multiply that value by the factor 9.371813e-25.
- The product is the equivalent value in drams (avoirdupois) (dr).
- To reverse, multiply the dram (avoirdupois) value by 1.067029e+24.
Worked examples
Example 1 — Convert 1 u to dr:
1 × 9.371813e-25 = 9.371813e-25 dr
Example 2 — Convert 100 u to dr:
100 × 9.371813e-25 = 9.371813e-23 dr
Real-world example — From wavelengths to millimeter-scale objects
A value of one million atomic mass unit sounds vast at the atomic scale but converts to a small everyday quantity in drams (avoirdupois) — useful when relating optical-wavelength specifications to physical mounting hardware.
1000000 u × 9.371813e-25 = 9.371813e-19 dr
Real-world example — Sub-micron to millimeter
500,000 atomic mass unit converts to a small everyday quantity in drams (avoirdupois) — useful when relating optical-wavelength specifications to physical mounting hardware.
500000 u × 9.371813e-25 = 4.685907e-19 dr
Atomic Mass Unit to Dram (avoirdupois) conversion table
Standard reference values for converting atomic mass unit to drams (avoirdupois):
| Atomic Mass Unit [u] | Dram (avoirdupois) [dr] |
|---|---|
| 0.01 | 9.371813e-27 |
| 0.1 | 9.371813e-26 |
| 1 | 9.371813e-25 |
| 2 | 1.874363e-24 |
| 3 | 2.811544e-24 |
| 4 | 3.748725e-24 |
| 5 | 4.685907e-24 |
| 10 | 9.371813e-24 |
| 20 | 1.874363e-23 |
| 30 | 2.811544e-23 |
| 40 | 3.748725e-23 |
| 50 | 4.685907e-23 |
| 100 | 9.371813e-23 |
| 500 | 4.685907e-22 |
| 1000 | 9.371813e-22 |
Frequently asked questions
How many drams (avoirdupois) is 1 atomic mass unit?
How do I convert atomic mass unit to drams (avoirdupois)?
How do I convert drams (avoirdupois) back to atomic mass unit?
How many drams (avoirdupois) is 100 atomic mass unit?
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Metric / SI (18 units)
Avoirdupois (15 units)
Troy & Apothecary (10 units)
Indian / South Asian (6 units)
Scientific / Atomic (8 units)
Astronomical (4 units)
Biblical / Ancient (14 units)
Sources & references
Conversion factor (1 u = 9.371813e-25 dr) 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 Hydrographic Organization — Resolution on the Nautical Mile
International authority that standardised the nautical mile at exactly 1852 m in 1929 — the value adopted worldwide for sea and air navigation.