Electron Volt to Inch-Pound
eV
in·lb
Conversion History
| Conversion | Reuse | Delete |
|---|---|---|
| No conversion history to show. | ||
Quick Reference Table (Electron Volt to Inch-Pound)
| Electron Volt (eV) | Inch-Pound (in·lb) |
|---|---|
| 1 | 0.00000000000000000142 |
| 10 | 0.00000000000000001418 |
| 100 | 0.0000000000000001418 |
| 1,000 | 0.00000000000000141805 |
| 1,000,000 | 0.00000000000141804581 |
| 1,000,000,000 | 0.00000000141804581003 |
About Electron Volt (eV)
An electron volt (eV) is the kinetic energy gained by a single electron accelerating through an electric potential difference of one volt — equal to approximately 1.602 × 10⁻¹⁹ joules. It is the natural energy unit of particle physics, atomic physics, and chemistry, where joules would yield unwieldy powers of 10. Photon energies, ionisation energies, bandgaps in semiconductors, and masses of subatomic particles (via E = mc²) are all expressed in eV, keV, MeV, or GeV.
Visible light photons carry 1.8–3.1 eV of energy. The proton rest mass is 938 MeV. The Large Hadron Collider accelerates protons to 6.5 TeV (6.5 × 10¹² eV).
About Inch-Pound (in·lb)
The inch-pound (in·lb) is a unit of torque and small-scale energy used in US customary mechanical engineering, equal to approximately 0.11299 joules. It represents the work done by one pound-force over a distance of one inch, or equivalently, a torque of one pound-force acting at a radius of one inch. Small fastener torque specifications, precision instrument settings, and electronic component assembly instructions routinely use inch-pounds. It is 1/12 of a foot-pound.
A laptop hinge torque specification is often 2–5 in·lb. Small machine screws in electronics are typically torqued to 1–4 in·lb.
Electron Volt – Frequently Asked Questions
Why do particle physicists use electron volts instead of joules?
Because subatomic energies in joules have absurdly small exponents — a visible-light photon carries about 3 × 10⁻¹⁹ J, but a convenient 1.9 eV. The electron volt is scaled to the quantum world, making numbers human-readable. It also doubles as a mass unit (via E = mc²): a proton is 938.3 MeV/c², far easier to work with than 1.673 × 10⁻²⁷ kg.
How much energy in electron volts does visible light carry?
Visible light photons range from about 1.65 eV (deep red, 750 nm) to 3.1 eV (violet, 400 nm). Green light, where the human eye is most sensitive, sits around 2.3 eV. Ultraviolet photons start at 3.1 eV and can exceed 100 eV in the extreme UV. These energies are why UV can damage DNA (breaking molecular bonds of 3–5 eV) while visible light cannot.
What is the relationship between electron volts and semiconductor bandgaps?
A semiconductor's bandgap — the minimum energy to free an electron from its bond — is expressed in eV. Silicon has a bandgap of 1.12 eV, gallium arsenide 1.42 eV, and gallium nitride 3.4 eV. The bandgap determines which wavelengths of light a solar cell can absorb and what color an LED emits. Lower bandgap means longer-wavelength (redder) light.
How many electron volts does the Large Hadron Collider produce?
The LHC accelerates protons to 6.5 TeV (6.5 × 10¹² eV) per beam, giving collisions a center-of-mass energy of 13 TeV. That sounds enormous, but 13 TeV is only about 2 microjoules — the kinetic energy of a flying mosquito. The power of the LHC lies in concentrating that energy into a space a million times smaller than an atom.
How do you convert electron volts to joules?
Multiply by 1.602 176 634 × 10⁻¹⁹. So 1 eV = 1.602 × 10⁻¹⁹ J, 1 keV = 1.602 × 10⁻¹⁶ J, and 1 MeV = 1.602 × 10⁻¹³ J. This conversion factor is exactly the elementary charge in coulombs, because an electron volt is defined as the energy gained by one electron charge crossing one volt of potential.
Inch-Pound – Frequently Asked Questions
Why are small fastener torque specs given in inch-pounds instead of foot-pounds?
Inch-pounds provide finer resolution for small fasteners where foot-pound values would be fractions (e.g., 3 in·lb vs 0.25 ft·lb). Electronics assembly, firearms scope mounting, and bicycle component installation all specify inch-pounds because over-torquing a small screw by even one foot-pound can strip threads or crack housings.
What happens when you over-torque a small fastener by just 2 inch-pounds?
On an M3 screw into aluminum (spec: 5 in·lb), exceeding by 2 in·lb — a 40% overload — can strip the threads or crack a thin boss. Small fasteners have almost no safety margin because the thread engagement area is tiny and the materials (plastic, aluminum, brass) are soft. This is why electronics repair shops use beam-type or preset click torque drivers accurate to ±0.5 in·lb, and why aerospace assembly procedures treat inch-pound specs as hard limits, not suggestions.
What torque in inch-pounds do laptop and electronics screws need?
Laptop hinge screws typically require 2–5 in·lb, hard drive mounting screws 2–4 in·lb, and motherboard standoff screws 5–8 in·lb. Going beyond the spec risks cracking plastic bosses or stripping soft aluminum threads. A precision bit driver with a torque limiter is essential for electronics repair work.
What is the difference between inch-pounds as torque and inch-pounds as energy?
Dimensionally they are identical — force times distance — but context differs. As torque, 1 in·lb means one pound-force applied at one inch from a pivot. As energy, it means one pound-force pushing through one inch of linear displacement (0.11299 J). In practice, inch-pounds almost always refer to torque in mechanical specifications.
Why do firearms manufacturers specify scope ring torque in inch-pounds?
Scope rings and bases use small screws that are easily damaged, and consistent clamping force is critical for zero retention under recoil. Typical specs are 15–25 in·lb for ring screws and 30–65 in·lb for base screws. Under-torquing lets the scope shift; over-torquing cracks the scope tube or strips the screw. A dedicated inch-pound torque wrench is considered essential kit for precision rifle setup.