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What is a high resistance circuit?
AnswerThe resistance of a material depends on its length, cross-sectional area, and resistivity. This is expressed by the following equation:resistance = [(resistivity x length) / cross-sectional area]So, resistance is directly-proportional to the resistivity and length of the material, and inversely-proportional to its cross-sectional area. So a high resistance can be obtained by increasing the length of the material or by decreasing its cross-sectional area, or by choosing a material with a high resistivity.It's also worth pointing out that resistivity is affected by temperature. For pure metals, the higher the temperature, the higher the resistivity, so the higher the resisistance. For example, a hot (i.e. an operating) tungsten lamp will have a much higher resistance than a cold tungsten lamp.
Is the resistance lower if you have a high current?
Lower than what? For the same voltage, a lower resistance means higher current. But beware, the voltage itself might depend on the current - thus - with a fixed resistance if you change the voltage, you will increase the current in the same proportion. Some things become higher resistance if they get hot (a tungsten filament in a lamp). Other things become lower resistance if they get hot (semiconductors). So it can all depend on what kind of circuit you have.
Does plastic have a high resistance?
Yes, it has a high resistance as it is an insulator.
What is high resistance and low resistance?
Low resistance lets electrons through easy, and high makes it harder for them to pass. Basically electricity is harder to flow through high resistance and vice versa.
Why is the cathode ray tube's filament made of tungsten?
Because tungsten has a high melting point. This allows it to be heated red/white hot without melting. This high temperature results in the thermionic emission (boiling off) of electrons which are needed for the CRT to work. Tungsten also has a low vapour pressure at high temperatures, so it won't evaporate too quickly, and it is relatively cheap.
What is a good conductor and has high resistance?
tungsten
Does tungsten have high resistance?
Wolfram (tungsten) is resistant to attack of other chemicals as many acids, alkalis and oxygen.
What is the defect if you use tungsten for domestic wiring?
Because tungsten is having high resistance and therefore heat loss will be more
Why tungsten is not as heating element in iron box?
tungsten has high resistivity and resistance but at a higher temperature it becomes hot and oxidised and melted so we can't use tungsten as heating coil
What are novel applications of tungsten alloys?
The hardness and heat resistance of tungsten can contribute to useful alloys. Tungsten's high melting point makes tungsten a good material for applications like submarine ballistics. Tungsten alloys are used in a wide range of applications, including the aerospace and automotive industries and radiation shielding.Superalloys containing tungsten, such as Hastelloy are used in turbine blades and resistants. Tungsten's heat resistance makes it useful in composite applications as can be a highly-conductive metal to withstand the high temperatures.
What is pure tungsten?
As a high performance material, pure tungsten has high melting temperature, high density, low vapor pressure, low thermal expansion combined with good thermal conductivity, sufficient electrical resistance and high modulus of elasticity.
What are some devices that are wired such that they have a high resistance in order to create heat?
A light bulb is the best example. The tungsten creates such a high resistance that all the accumulated heat produces light energy.
Why is tungsten used in cutting tools?
Tungsten is used in cutting tools primarily because it has very high corrosion resistance. Most mineral acids barely even damage the metal.
Light bulbs how does running electricity through the bulb create light?
The electricity runs through a coil of Tungsten. Tungsten has a very high resistance. As per Joule's Law, energy radiated is directly proportional to resistance. The energy radiated is so large that the coil starts to glow and light is produced.
What is a high resistance circuit?
AnswerThe resistance of a material depends on its length, cross-sectional area, and resistivity. This is expressed by the following equation:resistance = [(resistivity x length) / cross-sectional area]So, resistance is directly-proportional to the resistivity and length of the material, and inversely-proportional to its cross-sectional area. So a high resistance can be obtained by increasing the length of the material or by decreasing its cross-sectional area, or by choosing a material with a high resistivity.It's also worth pointing out that resistivity is affected by temperature. For pure metals, the higher the temperature, the higher the resistivity, so the higher the resisistance. For example, a hot (i.e. an operating) tungsten lamp will have a much higher resistance than a cold tungsten lamp.
What are uses for tungsten?
There are many uses for tungsten: Incandescent light bulbs: It makes up the filament of the bulb. It is used in the bulb because it can withstand extreme temperatures. Jewelry: The high scratch resistance and dark shine of tungsten makes it a very popular choice among men for rings and bracelets. Abrasive Coating: Many tools subject to cutting hard metals in harsh conditions are coated with tungsten. The high melting point and hardness of tungsten make it a valuable asset to machinery and cutting tools.
What is the luster of tungsten?
Tungsten has a medium to high luster, shines like silver
