Three Ways to Measure Tiny Things


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Measurements are an important part of our daily lives, even if we don’t realize it. For example, when we need to go somewhere unfamiliar, we use a map or GPS to get there. Maps must have the correct measurements to translate real distances to a viewable scale. GPS (Global Positioning Systems) use satellites above the Earth and receivers on the Earth to track where you are in relation to where you need to be. The application of measuring goes well beyond travel, however. For buildings to be structurally sound, precise measurement must be done before and during construction. Production lines of just about any product imaginable requires accurate measurement of size and weight as well.

Using relations and clever mathematics we can measure just about everything, even things colossal in size like the circumference of the Moon or even the mass of far away stars and galaxies. But if the largest objects in the universe can be measured, what about the smallest? We could go into the complexities physicists go through to determine the size of atoms and things even smaller than that, but for our purposes we can consider something like a grain of salt. How can a particle so small even get measured, and why does it matter anyway?

Minuscule Measurements Matter
The importance of measuring these small things becomes apparent when you consider the amount of such things we consume. Pharmaceutical drugs, for instance, often come in powder form. The amount of the drug needs to be measured very precisely to ensure proper dosage as well as the safety of the user. Additionally, many cosmetic products feature powders and small particles. When dealing with such tiny particles, certain things have to be considered, such as the content of the power itself. In other words, how much of what material is in said powder? It can be hard to tell on such a small scale whether or not harmful material is present, or too much of something is in there. There are ways for analyzing these things, and it’s at the root of measuring minuscule matter.

Particle Size Distribution Analysis

Particle size distraction analysis refers to a method by which particles, whether in powder form, granular form, or dispersed in fluid, are measured by their mass. In other words, it’s a way of seeing how much of something makes up a powder or something like it. So how is it done? Well, there are many ways of going about particle size distribution analysis depending on several factors such as average particle size, type of material, and amount of time available for such measurement. Here are three major methods of particle size distribution analysis.

1) Laser Diffraction Testing

This method relies on the property of matter that states its size is directly proportional to the intensity of light scattered by it. A laser beam is sent through an incredibly small object (millimeters to nanometers), measuring its geometry. From there, its size can be determined. The accuracy and speed at which these tiny particles can be measured via laser diffraction analysis has made it one of the most used and effective methods of particle size distribution analysis today.

2) Electron Microscopy Images

Electron microscopes are basically super-powered microscopes that use a beam made up of highly accelerated electrons to measure objects unseeable by the human eye alone. These tools can identify tiny details as well as measure small particles and reveal their structure, shape, and other properties. This method is useful for actually seeing the detailed difference in size between particles in a substance.

3) Sieve Analysis

This method is one of the oldest used for particle size distribution analysis. Sieves are tools that filter out particles by their size. A typical sieve has several small pore-like holes that allow materials smaller than the hole to escape and the larger ones to remain inside. By stacking several sieves with different sized pores, materials can be physically separated by their size. With enough sieves, relatively accurate measurements can be made on the size of particles within a powder, such as soil. This method isn’t as accurate as laser diffraction or electron microscopy when it comes to measuring individual particles, but it’s still an effective way of initially separating particles by size before going into more detailed measurements.