Why Does a Sharp Knife Cut Better?

Why Does a Sharp Knife Cut Better?

It may seem obvious, but do you actually understand why a sharp knife cuts better than a blunt one? We’ll give you the science behind why it is essential to keep your knives sharp. 

Why is a sharp knife more effective

One word: Physics. 

It all comes down to the surface area upon contact and you do not need a knife to test this in practice. Take a fresh hamburger roll. If you apply downward pressure and squash the roll with the palm of your hand, what happens? 

Notice the roll spreads sideways as it is flattened. That is because the force of the palm pressing down on the bread means that the bread needs to move out of the way. Now try using the edge of your hand and apply the same downward movement. You’ll notice that the bread will collapse in on itself and you’ll leave a mark that will resemble that of the chop. This is because the edge of your hand has less surface area, and as a result the pressure is more. Therefore, it is easier to make your mark. 

This is the same concept that illustrates why a knife is so effective at cutting when compared to a blunter knife. In effect, when you are sharpening a knife with a product such as a whetstone sharpener, you are reducing the area of the knife. Because pressure = force/area, a knife with a smaller area will produce a more effective cut. 

What are the advantages of using a sharper knife?

Well it goes without saying that it will produce a more effective cut, but there is another key advantage behind using a sharp knife instead of a blunt one. Simply, it is safer. This may seem odd given that a sharper knife has the capability to do more damage but it is all about control. 

A blunt knife can lose traction and slip, making it easy to hurt yourself by accidentally cutting your finger. Conversely, a sharper knife will reliably cut through the point of entry, therefore giving the user greater control over the blade. 

Ensure to regularly sharpen your knife

It is important to undertake knife sharpening the moment that your knife starts being ineffective or you feel a loss of control and an increased risk of slipping. Investing in a knife sharpener is guaranteed to help extend the life of your knife while ensuring that it works to maximum effect. 

With so many knife sharpening options, it is easy to get lost when deciding which is worthy of investing in. To be honest, you can’t go wrong with: 

  • A whetstone sharpener
  • Electric Knife Sharpener
  • Manual Knife Sharpener
  • Sharpening Steel
However, the most popular is without doubt the Whetstone Sharpener. It is considered the most precise way to sharpen a knife. It receives such high praise due to the combination of precision and the careful touch exerted on the knife blade which ensures not only a sharpened knife but an undamaged knife.