Inch-Pound to Grams of TNT
in·lb
gTNT
Conversion History
| Conversion | Reuse | Delete |
|---|---|---|
1 in·lb (Inch-Pound) → 0.00002700402223413401 gTNT (Grams of TNT) Just now |
Quick Reference Table (Inch-Pound to Grams of TNT)
| Inch-Pound (in·lb) | Grams of TNT (gTNT) |
|---|---|
| 1 | 0.00002700402223413401 |
| 2 | 0.00005400804446826802 |
| 5 | 0.00013502011117067005 |
| 12 | 0.00032404826680960813 |
| 25 | 0.00067510055585335026 |
| 50 | 0.00135020111170670053 |
| 100 | 0.00270040222341340105 |
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.
About Grams of TNT (gTNT)
The gram of TNT (gTNT) is a unit of explosive energy equal to exactly 4,184 joules — the energy released by detonating one gram of trinitrotoluene. By convention, this is a defined unit; real TNT yields vary by about ±2% depending on formulation. It is used to characterize small explosive charges, improvised explosive devices, and the energy of chemical reactions involving explosives. One gram of TNT releases roughly the same energy as one dietary kilocalorie (thermochemical).
A standard firecracker releases energy equivalent to about 0.5–1 g of TNT. A hand grenade contains the explosive equivalent of roughly 60–90 g of TNT.
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.
Grams of TNT – Frequently Asked Questions
How much energy does one gram of TNT actually release?
By convention, exactly 4,184 joules — the same as one thermochemical kilocalorie. Real TNT detonation yields vary by about ±2% depending on purity and confinement, but the defined value provides a fixed reference point. This makes the gram of TNT a convenient bridge between chemistry (calories) and explosive engineering.
Why is TNT used as the standard reference for explosive energy?
TNT (trinitrotoluene) became the reference explosive because it is chemically stable, safe to handle, and was massively produced during both World Wars. Its consistent detonation properties made it a natural benchmark. Other explosives are rated by their "TNT equivalent" — for example, C-4 is about 1.34× TNT and ANFO is about 0.74× TNT.
How many grams of TNT equivalent does a firecracker contain?
A standard US consumer firecracker contains about 0.5–1 gram of TNT equivalent in flash powder. An M-80 (now illegal for consumer sale) contained roughly 3 g of TNT equivalent. Cherry bombs were about 1.5 g. Commercially sold fireworks are regulated by the CPSC to contain no more than 50 mg of flash powder per report charge.
What is the TNT equivalent of a hand grenade?
A US M67 fragmentation grenade contains about 180 g of Composition B explosive, which has a TNT equivalence of about 1.33×, giving roughly 240 grams of TNT equivalent. The lethal radius is about 5 meters, with a casualty-producing radius of 15 meters. The fragmentation — not the blast energy alone — is the primary wounding mechanism.
How does the gram of TNT relate to the calorie?
One gram of TNT releases exactly 1 thermochemical kilocalorie (1 kcal = 4,184 J) by definition. This means a dietary Calorie (nutritional kcal) contains the same energy as detonating one gram of TNT. A 2,000-Calorie daily diet is energetically equivalent to 2 kg of TNT — though your body releases that energy over 24 hours, not in microseconds.