Mass and Weight · Unit Converter

Convert Dram (apothecary/troy) to Electron Mass (rest)

Convert drams (apothecary/troy) to electron mass (rest) instantly. 1 dram (apothecary/troy) = 4.268052e+27 electron mass (rest) — use the live calculator, the exact formula, a conversion table and worked examples. Also check the Electron Mass (rest) to Dram (apothecary/troy) converter for the reverse conversion.

Written by Sunith Babu L, Ph.D., Lead Engineer Reviewed by Dr. Ashok Kumar K, Ph.D.
Mass and Weight category 2 min read Published Last reviewed Updated

Units explained

Troy & Apothecary

Dram (apothecary/troy)

What is a dram (apothecary/troy)?

The apothecary (troy) dram equals one-eighth of a troy ounce, about 3.888 grams.

Origin of the dram (apothecary/troy)

From the apothecaries' system rooted in the Greek 'drachma'.

Where it is used

Historical pharmacy and medicine compounding.

When and where it was developed

Part of the apothecaries' system of weights used through the 19th century.

Scientific / Atomic

Electron Mass (rest)

What is a electron mass (rest)?

The electron rest mass is about 9.109E-31 kg.

Origin of the electron mass (rest)

The mass of the electron, the lightest charged elementary particle.

Where it is used

Atomic and particle physics.

When and where it was developed

Quantified after J. J. Thomson identified the electron in 1897.

Dram (apothecary/troy) to Electron Mass (rest) conversion formula

Note: this conversion uses a generally accepted modern value. Historical and regional definitions of this unit varied across times and places.

The relationship between drams (apothecary/troy) and electron mass (rest):

1 dr ap = 4.268052e+27 me
1 me = 2.342989e-28 dr ap

To convert drams (apothecary/troy) to electron mass (rest), multiply the value in drams (apothecary/troy) by 4.268052e+27. To reverse, multiply electron mass (rest) by 2.342989e-28.

How to use this converter

Type a value into the calculator. The result in electron mass (rest) updates as you type. Tap a quick value, copy the result with one click, or use the swap arrow to jump straight to the Electron Mass (rest) to Dram (apothecary/troy) converter for the reverse direction.

Step-by-step: convert drams (apothecary/troy) to electron mass (rest)

  1. Write down the value in drams (apothecary/troy) (dr ap).
  2. Multiply that value by the factor 4.268052e+27.
  3. The product is the equivalent value in electron mass (rest) (me).
  4. To reverse, multiply the electron mass (rest) value by 2.342989e-28.

Worked examples

Example 1 — Convert 1 dr ap to me:
1 × 4.268052e+27 = 4.268052e+27 me

Example 2 — Convert 100 dr ap to me:
100 × 4.268052e+27 = 4.268052e+29 me

Real-world example — Centimeter to wavelength scale

One dram (apothecary/troy) equals 10 million electron mass (rest). Physics curricula use this kind of conversion to relate everyday measurements to atomic and optical scales.

1 dr ap × 4.268052e+27 = 4.268052e+27 me

Real-world example — Small-scale to atomic-scale

One dram (apothecary/troy) equals 10 million electron mass (rest) — useful for physics curricula that relate everyday measurements to atomic and optical scales.

1 dr ap × 4.268052e+27 = 4.268052e+27 me

Dram (apothecary/troy) to Electron Mass (rest) conversion table

Standard reference values for converting drams (apothecary/troy) to electron mass (rest):

Dram (apothecary/troy) [dr ap]Electron Mass (rest) [me]
0.014.268052e+25
0.14.268052e+26
14.268052e+27
28.536103e+27
31.280416e+28
41.707221e+28
52.134026e+28
104.268052e+28
208.536103e+28
301.280416e+29
401.707221e+29
502.134026e+29
1004.268052e+29
5002.134026e+30
10004.268052e+30

Frequently asked questions

How many electron mass (rest) is 1 dram (apothecary/troy)?
1 dram (apothecary/troy) equals 4.268052e+27 electron mass (rest).
How do I convert drams (apothecary/troy) to electron mass (rest)?
Multiply the value in drams (apothecary/troy) by 4.268052e+27 to get electron mass (rest).
How do I convert electron mass (rest) back to drams (apothecary/troy)?
Multiply the value in electron mass (rest) by 2.342989e-28, or use the Electron Mass (rest) to Dram (apothecary/troy) converter.
How many electron mass (rest) is 100 drams (apothecary/troy)?
100 drams (apothecary/troy) equals 4.268052e+29 electron mass (rest), because 100 × 4.268052e+27 = 4.268052e+29.

Convert Dram (apothecary/troy) to other weight units

Show all Dram (apothecary/troy) conversions
Metric / SI (18 units)
Dram (apothecary/troy) to Attogram (ag) Dram (apothecary/troy) to Femtogram (fg) Dram (apothecary/troy) to Picogram (pg) Dram (apothecary/troy) to Nanogram (ng) Dram (apothecary/troy) to Microgram (µg) Dram (apothecary/troy) to Milligram (mg) Dram (apothecary/troy) to Centigram (cg) Dram (apothecary/troy) to Decigram (dg) Dram (apothecary/troy) to Gram (g) Dram (apothecary/troy) to Dekagram (dag) Dram (apothecary/troy) to Hectogram (hg) Dram (apothecary/troy) to Kilogram (kg) Dram (apothecary/troy) to Quintal (metric) (q) Dram (apothecary/troy) to Metric Ton (t) Dram (apothecary/troy) to Gigagram (Gg) Dram (apothecary/troy) to Teragram (Tg) Dram (apothecary/troy) to Petagram (Pg) Dram (apothecary/troy) to Exagram (Eg)
Avoirdupois (15 units)
Dram (apothecary/troy) to Grain (gr) Dram (apothecary/troy) to Dram (avoirdupois) (dr) Dram (apothecary/troy) to Ounce (oz) Dram (apothecary/troy) to Pound (lb) Dram (apothecary/troy) to Clove (clove) Dram (apothecary/troy) to Stone (US) (st) Dram (apothecary/troy) to Stone (UK) (st) Dram (apothecary/troy) to Quarter (US) (qr) Dram (apothecary/troy) to Quarter (UK) (qr) Dram (apothecary/troy) to Hundredweight (US) (cwt) Dram (apothecary/troy) to Hundredweight (UK) (cwt) Dram (apothecary/troy) to Wey (wey) Dram (apothecary/troy) to Kilopound (kip) (kip) Dram (apothecary/troy) to Ton (short, US) (sh tn) Dram (apothecary/troy) to Ton (long, UK) (long tn)
Troy & Apothecary (9 units)
Dram (apothecary/troy) to Point (1/100 carat) (pt) Dram (apothecary/troy) to Carat (metric) (ct) Dram (apothecary/troy) to Scruple (apothecary) (s ap) Dram (apothecary/troy) to Pennyweight (dwt) Dram (apothecary/troy) to Momme (mom) Dram (apothecary/troy) to Mace (mace) Dram (apothecary/troy) to Troy Ounce (oz t) Dram (apothecary/troy) to Tael (tael) Dram (apothecary/troy) to Pound (troy/apothecary) (lb t)
Indian / South Asian (6 units)
Dram (apothecary/troy) to Ratti (ratti) Dram (apothecary/troy) to Masha (masha) Dram (apothecary/troy) to Tola (tola) Dram (apothecary/troy) to Chittack (Chatank) (chittack) Dram (apothecary/troy) to Seer (Ser) (seer) Dram (apothecary/troy) to Maund (Mann) (maund)
Scientific / Atomic (9 units)
Dram (apothecary/troy) to Electron Mass (rest) (me) Dram (apothecary/troy) to MeV/c2 (MeV/c²) Dram (apothecary/troy) to Muon Mass (mµ) Dram (apothecary/troy) to Atomic Mass Unit (u) Dram (apothecary/troy) to Proton Mass (mp) Dram (apothecary/troy) to Neutron Mass (mn) Dram (apothecary/troy) to Deuteron Mass (md) Dram (apothecary/troy) to Carbon-12 Atom Mass (C-12) Dram (apothecary/troy) to Planck Mass (mP)
Astronomical (4 units)
Dram (apothecary/troy) to Lunar Mass (Moon) (M☾) Dram (apothecary/troy) to Earth's Mass (M⊕) Dram (apothecary/troy) to Jupiter Mass (MJ) Dram (apothecary/troy) to Sun's Mass (M☉)
Biblical / Ancient (14 units)
Dram (apothecary/troy) to Lepton (Biblical Roman) (lepton) Dram (apothecary/troy) to Quadrans (Biblical Roman) (quadrans) Dram (apothecary/troy) to Assarion (Biblical Roman) (assarion) Dram (apothecary/troy) to Gerah (Biblical Hebrew) (gerah) Dram (apothecary/troy) to Drachma (Biblical Greek) (drachma) Dram (apothecary/troy) to Denarius (Biblical Roman) (denarius) Dram (apothecary/troy) to Bekan (Biblical Hebrew) (bekah) Dram (apothecary/troy) to Didrachma (Biblical Greek) (didrachma) Dram (apothecary/troy) to Shekel (Biblical Hebrew) (shekel) Dram (apothecary/troy) to Tetradrachma (Biblical Greek) (tetra) Dram (apothecary/troy) to Mina (Biblical Greek) (mina) Dram (apothecary/troy) to Mina (Biblical Hebrew) (mina) Dram (apothecary/troy) to Talent (Biblical Greek) (talent) Dram (apothecary/troy) to Talent (Biblical Hebrew) (talent)
Force / Engineering (5 units)
Dram (apothecary/troy) to Poundal (pdl) Dram (apothecary/troy) to Ton (assay) (US) (AT) Dram (apothecary/troy) to Ton (assay) (UK) (AT) Dram (apothecary/troy) to Kilogram-force square second/meter (hyl) Dram (apothecary/troy) to Slug (slug)

Sources & references

Conversion factor (1 dr ap = 4.268052e+27 me) verified against the following authoritative sources:

Results are provided for general reference. Verify critical measurements against an authoritative standard.