Question

The unit of pressure in the SI system is the pascal. What would be the SI name for 1 one-thousandth of a pascal?

Short answer

Answer: 1 millipascal (1 mPa)

Step-by-step solution

Understand the SI prefix system

In the SI (International System of Units) system, there are various prefixes used to represent decimal multiples and submultiples of a unit. In this case, we will look for the prefix that represents one-thousandth (1/1000).

Identify the appropriate SI prefix

The prefix for one-thousandth is "milli" (m), which represents a factor of 10^{-3}.

Convert pascal to millipascal

Now that we know the SI prefix for one-thousandth is "milli", we can convert 1 pascal to millipascal. To do this, multiply the value of pascal by the milli factor (\times10^{-3}): 1\,\text{Pascal} \times 10^{-3} = 1\,\text{millipascal}

Provide the final SI name

The SI name for 1 one-thousandth of a pascal is 1 millipascal (1 mPa).

Key concepts

Pressure

Pressure is an essential concept in physics and engineering. It describes the force exerted on a surface area. In simpler terms, pressure tells us how much force is distributed over a specific area.

• The formula for pressure is: \[ P = \frac{F}{A} \] where \( P \) is pressure, \( F \) is force, and \( A \) is the area over which the force is distributed.
• Pressure plays a crucial role in various applications, from hydraulic systems to weather forecasting.

When you press your finger against the table, the pressure exerted by your finger is the force you apply divided by the area of your fingertip. The smaller the area, the greater the pressure for the same force.
Understanding pressure helps us develop technologies like vacuum cleaners and air pressure gauges. It also helps in predicting weather patterns by understanding atmospheric pressure changes.

Pascal

The pascal is the SI unit of pressure. Named after the French mathematician Blaise Pascal, it quantifies the amount of force per unit area. One pascal is equal to one newton per square meter.

• The unit is represented by the symbol \( \text{Pa} \).
• Using the SI base units, 1 pascal is equal to \( \text{kg} \, \text{m}^{-1} \, \text{s}^{-2} \).

One pascal is a relatively small amount of pressure. Everyday applications often involve higher pressure units like kilopascals (kPa) or megapascals (MPa). For example, the standard atmospheric pressure at sea level is approximately 101,325 pascals or 101.325 kPa.
The pascal is favored for its simplicity in calculations when combined with other SI units. It harmonizes with length, mass, and time units for accurate measurement in science and engineering.
Understanding the pascal allows us to grasp how pressures work in real-world contexts, from measuring blood pressure to gauging tire pressure.

Milli-prefix

The milli-prefix is one of the prefixes used in the International System of Units (SI) to denote one-thousandth of a base unit. In symbols, milli is represented by the letter \( \text{m} \), and it scales a unit by the factor \( 10^{-3} \).

• This means that 1 millimeter (mm) is one-thousandth of a meter (m).
• Similarly, 1 milligram (mg) is one-thousandth of a gram (g).

These prefixes allow us to work with smaller, more manageable measurements without changing the unit's integrity. It's especially useful in scientific and engineering contexts where dealing with tiny quantities is common.
For the SI unit of pressure, using the milli-prefix, 1 pascal becomes 1 millipascal (mPa).This is crucial for applications needing precise pressure measurement, such as in microfluidics and materials science.

Unit Conversion

Unit conversion is the process of converting a measurement from one unit to another. This is essential for ensuring consistency and understanding when working across different systems or scales.

• In the metric system, conversion is often straightforward due to its base ten foundation.
• Factors of 10, like milli (\( 10^{-3} \)), simplify scaling quantities up or down.

To convert units such as pressure from pascal to millipascal, multiply by the conversion factor. For example, converting 1 pascal to millipascal involves multiplying by \( 10^{-3} \), which results in 1 mPa.
Understanding unit conversion is crucial for science and engineering disciplines. It allows coherent and consistent communication and documentation practices across various fields worldwide.
Becoming proficient in converting units helps ensure accuracy in experiments and real-world applications, ultimately contributing to advancements in technology and research.