What is the electron charge-to-mass ratio?
The electron charge-to-mass ratio is -e/m_e = -1.75882001076e11 C/kg (uncertainty ±5.3e1). The magnitude is 1.75882001076e11 C/kg.
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| Value | -1.75882001076e11 C/kg |
|---|---|
| Symbol | -e/m_e |
| Magnitude | 1.75882001076e11 C/kg |
| Uncertainty | ±53 C/kg |
| Source | CODATA 2018 |
Frequently asked questions
What is the electron's charge-to-mass ratio?
-e/m_e = -1.75882001076e11 C/kg, the value famously first measured by J.J. Thomson.
Why is the sign negative?
Because the electron carries negative charge; the magnitude is 1.75882001076e11 C/kg.
Why is e/m_e important?
It was key to discovering the electron and is used in mass spectrometry and cathode-ray analysis.
Related pages
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