Cutting is the separation or opening of a physical object, into two or more portions, through the application of an acutely directed force.
Implements commonly used for cutting are the knife and saw, or in medicine and science the scalpel and microtome. However, any sufficiently sharp object is capable of cutting if it has a hardness sufficiently larger than the object being cut, and if it is applied with sufficient force. Even liquids can be used to cut things when applied with sufficient force (see water jet cutter).
Cutting is a compressive and shearing phenomenon, and occurs only when the total stress generated by the cutting implement exceeds the ultimate strength of the material of the object being cut. The simplest applicable equation is:
stress
=
force
area
{\displaystyle {\text{stress}}={{\text{force}} \over {\text{area}}}}
or
τ
=
F
A
{\displaystyle \tau ={\frac {F}{A}}}
The stress generated by a cutting implement is directly proportional to the force with which it is applied, and inversely proportional to the area of contact. Hence, the smaller the area (i.e., the sharper the cutting implement), the less force is needed to cut something. It is generally seen that cutting edges are thinner for cutting soft materials and thicker for harder materials. This progression is seen from kitchen knife, to cleaver, to axe, and is a balance between the easy cutting action of a thin blade vs strength and edge durability of a thicker blade.
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This is my work so far:
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Hello everyone,
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P.S Design is attached
Homework Statement
My question. When studying conics, the parabola circle, and ellipse can be easily see by passing a plane through a double cone. The hyperbola is generated when the plane is passed through the double cone where it passes through the top and the bottom cone. My question is...
Hi all,
This is not exactly a homework question, more like for my own safety
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It has a straight cone and a plane that cuts it as shown in the image. What angle should the plane form with the base of the cone ?, so that the plane cuts the cone in 2 parts of equal volume.
I had a test today on my linear algebra class, and it's safe to say that I didn't get more than a seventy percent on it. I got the first two problems of the test down, but the last problem asked me to prove something involving linearly independent sequences, how if a vector isn't in the span of...
Homework Statement
Bildschirmfoto 2018-06-19 um 18.50.50.png
In the y-z plane there is an infinite long surface with charge density ##\sigma## that slices through a sphere with radius R. Determine the Flux.The Attempt at a Solution
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It is amazing that we throw away 38 million tonns of food each day, This thread is for tips on reducing food waste, how to use left overs etc.
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Good afternoon guys,
I want to discuss with you guys a few things...
So i already design a log cutting mechanism as you can see in the picture below. But there is so much defect on my mechanism..
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Good morning guys,
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Hello,
could someone explain to me, how I should cut a FeBa magnet, if it has one pole facing upward and the other downward so that the bloch wall would be across the entire length of the magnet. The dimensions of the magnet at hand are 152 x 102 x 52 mm. The bloch wall runs across the entire...
Hello,
I wanted to know, if someone knows of a realistic option of, how to cut barrium ferrite magnets without using a rock saw and without demagnetizing the magnet obviously?
Thanks in advance everyone.
Hi,
New to this forum so sorry if i am not posting in the right place.
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Hey all,
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Hello,
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http://www.iscar.com/Products.aspx/countryID/1/ProductID/32
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Hello - I've been trying to solve this for a little while, and feel I may not understand some core concepts required to solve the problem. If you have any ideas, please let me know! I would very much like to discuss how to solve this.
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Homework Statement
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Homework Statement
A helical spring of stiffness k is cut into two halves and a mass m is connected to the two halves. The natural time period of this system is found to be 0.5 sec. If an identical spring is cut so that one part is one-fourth and the other part is three-fourths of the original...
Homework Statement
Hi I require to compute the volume of a ellipsoid that is bounded by two planes. The first horizontal (xy) plane is cutting directly along the mid-section of the ellipsoid. The second horizontal plane is at a z = h below the first horizontal plane. The volume of the...
I know there is supposedly no such thing as a stupid question but this might make some of you reconsider if that is true.
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Hi Everyone.
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Hello, I was searching on this forum for a long time, now I have a problem with my homework and I should complete this till tomorrow, I could use some hand :) Please somebody led me some light, and I believe this will be useful for others.
Homework Statement
For a transmisson shaft (material...