Wavelength
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Wavelength
Is wavelength always converted into m or are there any instance where wavelength must be in nm?
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Re: Wavelength
Constance Newell wrote:Is wavelength always converted into m or are there any instance where wavelength must be in nm?
If the final answer is in nm then it should be in nanometers. The primary reason we convert it to m is to use formulas with constants which are oftentimes given in terms of m, kg, s... etc. Otherwise you'd have to convert the constants/other aspects of the formulas in terms of nm.
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Re: Wavelength
kg is an SI unit. Also, in de Broglie's equation, Planck's constant (in the numerator) has the units Js. Remember that J is equal to kg m^2 s^-2. We need to cancel the kg out with a kg in the denominator so that we can eventually get the unit m for wavelength.
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Re: Wavelength
When solving a problem, wavelength must always be written in terms of m, since the other variables in the equation would be in m. However, when writing the wavelength as the final answer, it should be converted to nm in order to determine the spectrum.
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Re: Wavelength
Wavelength must be written in m because it is the SI unit for length. However, sometimes the answer may ask you to convert the answer from meters to nanometers, so the value is not so small
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Re: Wavelength
Since the SI unit for distance is meters, nanometers would need to be converted. This would just make it easier to compute using the de Broglie relation because the speed of light units is in meters per second.
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Re: Wavelength
It would depend on what the question is asking, but other than that do what’s easiest for you
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Re: Wavelength
All wavelength equations would require you to convert to meters since that is an S.I. unit.
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Re: Wavelength
When doing calculations, wavelength should always be converted to meters in order to ensure that the correct SI unit is being used. However, when giving an answer dealing with wavelength, it's best to give the answer in nm as this is normally the length that they are given in. From what I know, radio wavelengths are the only ones that are sometimes given in nm rather than m because of how long then are. Hope this helps!
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Re: Wavelength
it depends on the question, but its a pretty easy conversion (1m=1x10^9nm) so i wouldnt fret too much about converting, just pay attention to the problem at hand :)
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Re: Wavelength
Hi! Does anyone have a good way to memorize the various wavelengths on the atomic spectrum?
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Re: Wavelength
Wavelength should be written in meters, since it that is the correct si units. It just happens that sometimes we get an answer like with x10^-9 meters, and that is the same thing as nanometers. So, it may just be easier to refer to our answer in nanometers. And visible light is mainly all x10^-9 so we often refer to it in nanometers. Hope this helps!
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Re: Wavelength
Wavelength is usually converted to m as the default. However, if the problem is asking for a different unit of measure then we would have to convert our answer.
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Re: Wavelength
The standard unit for wavelength is generally meters. However, we should convert to nm if the question asks.
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Re: Wavelength
Hi! When doing the calculations, wavelength will be in m. This is because the values of all the constants are in terms of meters. After finding the value of the wavelength in meters, it can be converted to nm. I would assume that the wavelength is in meters, but if the problem asks for the wavelength to be in nm, I would convert meters to nano meters (1nm=1x10^-9 m).
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Re: Wavelength
Taber Ball 1F wrote:Hi! Does anyone have a good way to memorize the various wavelengths on the atomic spectrum?
I like to relate the terms to the things that remind me of the term, like nanometer is like nine-o-meter, because it is 10^-9 m. Hope this helps!
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Re: Wavelength
Constance Newell wrote:Is wavelength always converted into m or are there any instance where wavelength must be in nm?
When doing calculations, it usually needs to be in the SI unit of m. It may ask for a conversion in the end of the problem though. Hope this helps!
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Re: Wavelength
A general rule of thumb is to use m instead of nm for solving for photoelectric effect problems or de brogile problems. However, when you are solving for atomic spectra type of problems, you should be using nm.
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Re: Wavelength
Usually what I do is see what the equation I'm using is, because I want the units to be able to cancel; this usually helps me make my decision!
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Re: Wavelength
Wavelength should be in meter because all equations usually take measures of length in meters
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Re: Wavelength
Wavelength is typically converted to meters for calculations because the meter is the base unit for length. This results in most other units (such as Joules) using meters.
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Re: Wavelength
You always want to base your answer off of what the question is asking for, but in order to do calculations, most have to be done with the units in meters.
Re: Wavelength
It depends on what the question is asking for, sometimes it asks for nm but most of the time it asks for it in meters. However, if you were to use it in other calculations, make sure it is always in meters.
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Re: Wavelength
Determining spectrum would be a good example of nm, but I'm sure in experimentation it isn't hard to switch between the two at all.
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