Bar to Newton per Square Centimeter
bar
N/cm²
Conversion History
| Conversion | Reuse | Delete |
|---|---|---|
1 bar (Bar) → 10 N/cm² (Newton per Square Centimeter) Just now |
Quick Reference Table (Bar to Newton per Square Centimeter)
| Bar (bar) | Newton per Square Centimeter (N/cm²) |
|---|---|
| 0.01 | 0.1 |
| 0.1 | 1 |
| 1 | 10 |
| 2 | 20 |
| 10 | 100 |
| 100 | 1,000 |
| 300 | 3,000 |
About Bar (bar)
The bar equals exactly 100,000 pascals — approximately 1.3% less than standard atmospheric pressure. It is widely used in engineering, hydraulics, industrial gas systems, and compressed-air applications, particularly in Europe and internationally. Tire pressures, hydraulic system operating pressures, scuba cylinder pressures, and industrial gas supplies are commonly quoted in bar. The bar is not an SI unit but is formally accepted for use alongside SI. Its decimal prefixes — millibar for meteorology, kilobar for high-pressure research — extend its range across many disciplines.
Car tire inflation is typically 2.0–2.5 bar. Scuba diving cylinders are filled to 200–300 bar.
About Newton per Square Centimeter (N/cm²)
The newton per square centimeter (N/cm²) equals exactly 10,000 pascals. It is used in materials testing and mechanical engineering for compressive stress, tensile strength, and contact pressures at scales where pascals produce unwieldy six-digit values but megapascals are too coarse. Machine tool specifications, polymer yield strengths, and some hydraulic standards cite pressures in N/cm². One N/cm² is approximately one-tenth of standard atmospheric pressure.
The compressive strength of ordinary concrete is roughly 2–5 N/cm². A car tire contact patch experiences about 1.5–3 N/cm² of ground pressure.
Bar – Frequently Asked Questions
Why do European tire gauges show bar while American ones show psi?
Europe adopted metric units broadly in the 19th and 20th centuries, and the bar (100,000 Pa) became the natural metric pressure unit for everyday engineering. The US never metricated, so pounds per square inch persisted. A car tire at 2.2 bar is the same as 32 psi — most modern tire placards list both. If you rent a car abroad and the pump reads bar, just divide your usual psi number by 14.5.
How many bar of pressure can a scuba tank hold?
Standard aluminum scuba cylinders are rated to 200 bar (2,900 psi); steel tanks often go to 232 or 300 bar. At 200 bar, the air inside is compressed to 1/200th of its surface volume — a 12-liter tank holds 2,400 liters of breathing gas. Deep technical divers using trimix may use 300-bar steel tanks to maximize bottom time at extreme depths.
Is one bar the same as one atmosphere?
Close, but not quite. One bar is exactly 100,000 Pa; one standard atmosphere is 101,325 Pa — about 1.3% higher. The bar was designed as a round-number metric unit, not an exact atmospheric equivalent. For most practical purposes (cooking, tire inflation, diving rules of thumb) the difference is negligible, but in chemistry and calibration work the distinction matters.
What bar pressures are common in industrial and everyday settings?
Espresso machines run at 9 bar, car tires at 2–2.5 bar, a fire extinguisher at 12–15 bar, a garden pressure washer at 100–150 bar, and a diesel fuel injection rail at up to 2,500 bar. The range from gentle (carbonated water at 2–4 bar) to extreme (waterjet cutting at 4,000+ bar) makes the bar a versatile everyday engineering unit.
Why is the bar not an official SI unit even though it is metric?
The SI only recognizes base and coherently derived units — pressure in SI is strictly the pascal (kg·m⁻¹·s⁻²). The bar is accepted "for use with SI" but is technically an outside unit, like the liter or the hour. The reason it thrives anyway is convenience: 2.2 bar is far friendlier than 220,000 Pa for a tire label, and industry adoption is too deep to reverse.
Newton per Square Centimeter – Frequently Asked Questions
When would an engineer use N/cm² instead of megapascals or bar?
N/cm² sits in a sweet spot for materials testing and contact mechanics. Concrete compressive strength (2–5 N/cm²), rubber hardness testing, and tire contact patch pressures all land in single- or double-digit N/cm² values. Megapascals would give fractions; bare pascals would give five-digit numbers. The unit is not common in consumer contexts, but it shows up on lab equipment and technical data sheets for polymers and composites.
How do you convert N/cm² to more common pressure units?
1 N/cm² = 10,000 Pa = 10 kPa = 0.1 bar ≈ 1.45 psi. The factor of 10,000 comes from the area: one square centimeter is 0.0001 m², so concentrating a newton on that smaller area multiplies the pressure by 10,000 compared with N/m². For quick field estimates, just remember 1 N/cm² ≈ 1.5 psi.
What is the pressure under a car tire in N/cm²?
Typical car tire inflation pressure is 2.0–2.5 bar, which is 20–25 N/cm². But the ground contact pressure depends on tire design and load distribution — it is usually close to the inflation pressure, so roughly 2–3 N/cm² for a passenger car. Heavy trucks with higher inflation pressures can exert 6–8 N/cm², which is why truck-rated roads need thicker pavement.
Is N/cm² related to the old "kilogram-force per square centimeter" unit?
Yes — 1 kgf/cm² ≈ 9.81 N/cm². The kgf/cm² was popular in older engineering because 1 kgf equals the force of gravity on 1 kg, making it intuitive. The N/cm² is the metrically cleaner successor: it uses newtons (SI force) instead of kilogram-force (a non-SI unit). In practice you will see both on older Asian and European equipment.
What N/cm² values represent the strength of common materials?
Soft rubber fails at about 1–2 N/cm². Ordinary concrete withstands 2–5 N/cm² in compression. Hardwood can take 4–6 N/cm². Mild steel yields at roughly 25,000 N/cm² (250 MPa). These numbers show why materials scientists prefer MPa for metals and GPa for ceramics — N/cm² stays practical mainly for softer materials and moderate-pressure systems.