You’ve probably come across the word viscosity several times and said to yourself: no, this is not for me. So, we’ve decided to show you why it’s actually for you and how you can apply it to your daily life. 

From the toothpaste in your bathroom to the honey you love so much, we’ll show you how viscosity plays a significant role in their production. Let’s dive right in. 

Viscosity: The Basics

Understanding the concept of viscosity seems like rocket science to many people. It looks like one of those complicated words that are only useful to scientists, which couldn’t be any further from the truth. Viscosity is one of the most critical properties to study in a fluid.  

But, you need to have the fundamental knowledge of viscosity to understand how it applies to you. And, for that, we’ve got just what you need. Here’s a simple definition of viscosity: the measurement of a fluid’s thickness. Each liquid (including glass in a molten state) has what we call molecules. When subjected to an external force, these molecules react in a specific way, leading to either an increase or decrease in viscosity. You can then calculate the viscosity using Newton’s equation for fluids.  

It is worth noting that, this formula can only be used for Newtonian liquids such as water and motor oil.  For non-Newtonian fluids like ketchup, another formula can be used to determine their viscosity. All this shows why it is important to know which liquid you’re dealing with and what viscometer best suits you. As we said earlier, each fluid reacts to external forces uniquely. This is why, before using any viscometer, you must ensure it is calibrated. Viscometer calibration, when done incorrectly, has a significant impact on the quality of the products. 

Temperature and Glass Viscosity

Have you ever wondered why glassblowers need to heat the glass to extreme temperatures before working with it? It may seem obvious, but there is a scientific reason for that. Glass has an interesting relationship with temperature. While most fluids have a higher viscosity when brought to high temperatures, glass does just the opposite. 

When a piece of glass is heated, in the beginning, it will absorb a large amount of heat energy to get to its melting point. As the thermal energy increases, the bonds holding the glass molecules break, causing the molecules to move faster, decreasing viscosity. 

With a reduced viscosity, glass becomes easy to handle and shape. But, to get to this point, you need to accurately measure the viscosity of the piece of glass you want to use. 


Watching a glassblower slowly mould a fuming, shapeless piece of glass into something beautiful is an amazing experience. They make it look so easy you might think everyone can become a glassblower. 

With the knowledge you’ve gained on glass viscosity and how it is measured, you will be able to appreciate even more each piece of glass art you come across.