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Cross sectional area? what does this mean?

Cross sectional area? what does this mean? Topic: Pi case screen
June 17, 2019 / By Sabrina
Question: i have heard the term cross sectional area often. What does this mean? For example , take a copper wire which is cylindrical in shape and cross sectional area refers to which part of the wire? Do the circular tip is the cross sectional area of this wire? Thanks in advance.
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Best Answers: Cross sectional area? what does this mean?

Netta Netta | 3 days ago
Look at a slice of white bread. The white part of that slice is the cross sectional area of the loaf of bread that the slice came out of. Another way to look at it is end on. When looking directly at one end of that loaf you are looking at its cross sectional area, which is the same area as that slice. Take a cylinder and slice through it like you were slicing a slice of bread off its loaf. You slice across the loaf and the cylinder. And that why they are called "cross" sections and "cross" sectional areas. Basically a cross sectional area is whatever area you see after cutting across a body. Remember, as an area, its units are m^2 or ft^2 or similar length square units. Here's one more, important, example that might help you with the "tip" issue. Take a solid cone and look directly at its base. That circular area you see of the base is the cone's cross sectional area when the cross cut is perpendicular to the height of the cone. That area is A = pi R^2, where R is the radius of the base. I think that's probably obvious, but here's the point. When turning the cone around and looking straight on at its pointy side, the cross sectional area is exactly the same cross sectional area you saw when looking at the circular base. One more time. The cross sectional area of a cone when looking at its point is the same cross sectional area we see when looking at its base. All that depth, the height, of the cone when looking at the pointy end does not alter the cross sectional area. Both areas are A = pi R^2 where R is the radius of the cone's base. This results because the cross sectional area is really defined by a projection, a 2D shadow, of an object's cross section. And the cone will cast a circular shadow of the same size when the cone is pointing toward the screen and when it is pointing away from it. If I lost you here, sorry; you will learn about projections in vectors when you take that course. In any case, the projection of the wire at the tip, would be the shadow of a circle. The same circle we'd have if we sliced across the length of the wire somewhere in the middle. So, my point, is that the cross sectional area is still the same on the tip... up to a point... pun intended. Clearly if the "tip" is a very long tapering wire, there will be various cross sections areas, depending on where one slices the wire. But the small little nub at the end of a wire should not make much difference in the grand scheme of things.
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Netta Originally Answered: Cross sectional area? what does this mean?
Look at a slice of white bread. The white part of that slice is the cross sectional area of the loaf of bread that the slice came out of. Another way to look at it is end on. When looking directly at one end of that loaf you are looking at its cross sectional area, which is the same area as that slice. Take a cylinder and slice through it like you were slicing a slice of bread off its loaf. You slice across the loaf and the cylinder. And that why they are called "cross" sections and "cross" sectional areas. Basically a cross sectional area is whatever area you see after cutting across a body. Remember, as an area, its units are m^2 or ft^2 or similar length square units. Here's one more, important, example that might help you with the "tip" issue. Take a solid cone and look directly at its base. That circular area you see of the base is the cone's cross sectional area when the cross cut is perpendicular to the height of the cone. That area is A = pi R^2, where R is the radius of the base. I think that's probably obvious, but here's the point. When turning the cone around and looking straight on at its pointy side, the cross sectional area is exactly the same cross sectional area you saw when looking at the circular base. One more time. The cross sectional area of a cone when looking at its point is the same cross sectional area we see when looking at its base. All that depth, the height, of the cone when looking at the pointy end does not alter the cross sectional area. Both areas are A = pi R^2 where R is the radius of the cone's base. This results because the cross sectional area is really defined by a projection, a 2D shadow, of an object's cross section. And the cone will cast a circular shadow of the same size when the cone is pointing toward the screen and when it is pointing away from it. If I lost you here, sorry; you will learn about projections in vectors when you take that course. In any case, the projection of the wire at the tip, would be the shadow of a circle. The same circle we'd have if we sliced across the length of the wire somewhere in the middle. So, my point, is that the cross sectional area is still the same on the tip... up to a point... pun intended. Clearly if the "tip" is a very long tapering wire, there will be various cross sections areas, depending on where one slices the wire. But the small little nub at the end of a wire should not make much difference in the grand scheme of things.
Netta Originally Answered: Cross sectional area? what does this mean?
A cross section is the two-dimensional slice you would get by cutting through the object with a plane. A cylindrical wire has a circular cross section. (If cut the normal way. If you cut it lengthwise, the cross section would be a long skinny rectangle.) Of course, cross sectional area means the area of the cross section.

Luella Luella
A cross section is the two-dimensional slice you would get by cutting through the object with a plane. A cylindrical wire has a circular cross section. (If cut the normal way. If you cut it lengthwise, the cross section would be a long skinny rectangle.) Of course, cross sectional area means the area of the cross section.
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Luella Originally Answered: There was NEVER a cross.it was a stake.sorry folks?
In spite of the overwhelming symbolism of the cross, the precise shape of the object on which Jesus was crucified cannot be proven explicitly from the Bible. The Greek word translated “cross” is stauros, meaning “a pole or a cross used as an instrument of capital punishment.” The Greek word stauroo, which is translated “crucify” means to be attached to a pole or cross. Though the Greek usage of these words can mean “pole” or “stake,” many scholars argue that Jesus most likely died on a cross in which the upright beam projected above the shorter crosspiece. Biblically, though, an airtight case cannot be made for either a cross or a pole/stake. The Romans were not picky in regards to how they would crucify people. The Romans used crosses, poles, stakes, upside-down crosses, x-shaped crosses, walls, roofs, etc. Jesus could have been crucified on any of these objects and it would not have affected the perfection or sufficiency of His sacrifice. Certain cults, most notably the Jehovah’s Witnesses, are adamant that Jesus did not die on a cross, and that the cross is in fact a pagan symbol. Equally adamant are Christians who, in an effort to refute the Witnesses’ doctrines, cling to the idea of the cross and deny the pole/stake theory. While Jehovah’s Witnesses might be correct in their argument that Jesus was not crucified on a cross, that absolutely does not give any credence to their other beliefs, such as their denial of the deity of Christ. The truth is that we cannot definitively—from the Scriptures—make the case that Jesus died on a cross or a pole/stake. We just don’t know which Jesus was nailed to. In the end, such arguments only serve to get us off our message, which is that Jesus died on something and that His death is the sole atoning sacrifice for our sins (1 John 2:2). Crucifixion was probably the most horrible form of capital punishment ever devised by man. It was designed to be a lingering death. The victim, as a rule, was first subjected to flagellation, that is, a beating with a three-thong whip (fashioned of plaited leather, and studded with bone and metal). He was stripped naked and then secured with leather ties. Roman executioners had perfected the art of slow torture while keeping the victim alive. Some victims even lingered until they were eaten alive by birds of prey or wild beasts. Most hung on the cross for days before dying. When the legs would no longer support the weight of the body, the diaphragm was constricted in a way that made breathing impossible. That is why breaking the legs would hasten death (John 19:31-33), but this was unnecessary in Jesus’ case because He, not the Romans, chose the moment of His death (John 19:30). A notable feature of crucifixion was the stigma of disgrace that was attached to it (Galatians 3:13; 5:11; Hebrews 12:2). One indignity was the humiliation of carrying one’s own cross. After the beating, the soldiers would escort the prisoner through the crowds to the place of crucifixion. A placard bearing the indictment would be hung around the person’s neck. Here again we see the picture of Christ carrying the indictment of “sinner” for us which we ourselves would have to carry if it were not for Him. The death sentence we rightly deserve was carried out on Him so that we could go free. “He himself bore our sins in his body on the tree, so that we might die to sins and live for righteousness; by his wounds you have been healed” (1 Peter 2:24). Completely lost in arguments over the shape of the cross is its significance to us. Jesus said to His disciples, and by extension, to us, “If anyone would come after me, he must deny himself and take up his cross and follow me. For whoever wants to save his life will lose it, but whoever loses his life for me will find it” (Matthew 16:24-25). The cross/stake/pole was an instrument of death, and by telling us to take up our cross and follow Him, Jesus is revealing to us that in order to be His true followers, we must die to self. If we call ourselves “Christians,” then we must deny ourselves and give up our lives for His sake. This may take the extreme form of being martyred for our faith, but even in the most peaceful political settings, we must be willing to lose the self—crucifying self-righteousness, self-promotion, selfish ambitions—in order to be His followers. Those who are not willing are “not worthy” of Him (Matthew 10:38). So, did Jesus die on a cross? Maybe. Was it a pole or stake? Possibly. But, frankly, the shape of the object on which Jesus was crucified does not matter. What does matter is that Jesus died for our sins and that His death purchased for us eternal life. MIMI
Luella Originally Answered: There was NEVER a cross.it was a stake.sorry folks?
Jesus died on the cross.. why do some people take that negative energy and make it a stake. You see, holy trinity christians believe that our sins are forgiven when Jesus died n shed blood on the cross. If he died on a stake, then the bible is a lie, not worthy to believe and satan won the war.. that Jesus is not god.

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