Unit for Wavelength


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Yazmin Bocanegra 3L
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Unit for Wavelength

Postby Yazmin Bocanegra 3L » Fri Oct 18, 2019 12:56 am

Since "Hz" is for frequency and "m/s" is for speed, is there a label/unit for wavelength?

AnnikaMittelhauser4E
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Re: Unit for Wavelength

Postby AnnikaMittelhauser4E » Fri Oct 18, 2019 1:00 am

The standard unit for wavelength is just meters since it is a distance. You should have wavelength in meters when doing calculations so the units will cancel properly. However, often we are given the value in nanometers (in which case you'd want to convert the value to meters as your first step) or asked to give the answer in nanometers (in which case you'd convert your answer to nanometers in the last step).

andrewcj 2C
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Re: Unit for Wavelength

Postby andrewcj 2C » Fri Oct 18, 2019 1:22 am

Wavelength refers to the length of a wave, which is measured in meters. Just in case you needed the conversions, 1 nm = 10^-9 m. I also think that these conversions will be provided on tests.

005206171
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Re: Unit for Wavelength

Postby 005206171 » Fri Oct 18, 2019 1:38 am

wavelength is just measuring one peak to the next so this distance is in meters

Kassidy Ford 1I
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Re: Unit for Wavelength

Postby Kassidy Ford 1I » Fri Oct 18, 2019 9:09 am

while nanometers is common for wavelength, so is picometers, or leaving your answers in meters. honestly you could leave it in any unit of meters you want, lol

ValerieChavarin 4F
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Re: Unit for Wavelength

Postby ValerieChavarin 4F » Fri Oct 18, 2019 6:28 pm

Wavelength is measured in meters or other prefixes of meters such as nano and pico. It's easy to remember that units should cancel, c=λν which essentially is (m/s)=m x s^(-1)

Donna Nguyen 2L
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Re: Unit for Wavelength

Postby Donna Nguyen 2L » Fri Oct 18, 2019 8:58 pm

The unit for wavelength is meters. Although, it can be seen in nanometers, kilometers, picometers, etc.

Jasmine Summers 4G
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Re: Unit for Wavelength

Postby Jasmine Summers 4G » Fri Oct 18, 2019 11:20 pm

In problems, nm are often used because wavelengths are so small. However, make sure that you're using meters for the calculations because that is the SI unit used.

Megan Cao 1I
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Re: Unit for Wavelength

Postby Megan Cao 1I » Sat Oct 19, 2019 12:22 am

the unit for wavelength is in meters, or more commonly nanometers, nm (10^-9 m)
you can see this in the equation c=frequency x wavelength. if you rearrange the equation for wavelength you get c/frequency. the units for speed of light are m/s and the unit of frequency is s^-1. so the seconds cancel out and you're left with meters.

Kaitlyn Jang 1F
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Re: Unit for Wavelength

Postby Kaitlyn Jang 1F » Sat Oct 19, 2019 8:51 am

Wavelength is measured in meters, however some questions give or ask for the wavelength in nanometers. In the case that it does give nanometers of wavelength, just make sure to convert it to meters (nm x 10^-9) so that you can get the correct answer since the speed of light also has a unit of m/s and frequency is s^-1.

Kishan Shah 2G
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Re: Unit for Wavelength

Postby Kishan Shah 2G » Sat Oct 19, 2019 11:48 am

Usually when you are doing calculations using the equations related to this unit and you cancel out all the units you are left with meters when you are solving for wavelength. However, a lot times the questions want you to convert this answer into nanometers since the most common way to report wavelength is in nanometers. To summarize, the answer you get from the equation will be in meters, and you may have to or you may want to convert to nanometers.

MBouwman_4A
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Re: Unit for Wavelength

Postby MBouwman_4A » Sat Oct 19, 2019 8:54 pm

The standard unit for wavelength is meters (m). However it is often shown in problems as picometers (pm), nanometers (nm), or even Angstroms (A).

504939134
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Re: Unit for Wavelength

Postby 504939134 » Sun Oct 20, 2019 12:02 am

It is measured in meters, it is a distance. You can give it in picometers, and nanometers as well.

san_2F
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Re: Unit for Wavelength

Postby san_2F » Sun Oct 20, 2019 12:05 am

it's usually measured in meters but sometimes, problems can ask for it in nanometer, picometers, or angstroms.

Andrea_Torres
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Re: Unit for Wavelength

Postby Andrea_Torres » Sun Oct 20, 2019 12:27 pm

The unit for wavelength is in meters but sometimes for some problems nanometers is used.

Areena H 2K
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Re: Unit for Wavelength

Postby Areena H 2K » Sun Oct 20, 2019 1:28 pm

Typically I was told in discussion that wavelengths are given in nm but meters are used as well and picometers.

aishwarya_atmakuri
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Re: Unit for Wavelength

Postby aishwarya_atmakuri » Sun Oct 20, 2019 1:31 pm

The standard unit for wavelength is m, and this is the output of equations relating to light. However, nanometers (10^-9) are also a common unit of measurement.

Sally kim 4F
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Re: Unit for Wavelength

Postby Sally kim 4F » Sun Oct 20, 2019 1:35 pm

The unit for wavelength is m, since it is just a measurement of distance. Nanometers and picometers are both also alright in terms of using units.

kendal mccarthy
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Re: Unit for Wavelength

Postby kendal mccarthy » Sun Oct 20, 2019 1:52 pm

Hi! It seems mostly the wavelength, distance from peak to peak, is measured in nm, nanometers, on most of the diagrams in the book for the EM spectrum. But I'm sure maybe the tests will have us convert units to use in other equations.

Noah Canio 3C
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Re: Unit for Wavelength

Postby Noah Canio 3C » Sun Oct 20, 2019 2:00 pm

As mentioned by people in this thread, it looks like wavelength is going to measured in nm (nanometers). If you remember the equation:

speed of light = frequency*wavelength

You should notice that the speed of light has the units (meters/second).

Since frequency is cycles per second or (per second), it would make sense for wavelength to have units that are related to length (meters).

Cynthia Rodas 4H
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Re: Unit for Wavelength

Postby Cynthia Rodas 4H » Sun Oct 20, 2019 2:33 pm



The standard units are:

c= Speed of Light in meters per second (m/s)
= wavelength in meters (m)
= frequency in Hertz (Hz or 1/s)

However, the wavelength can be in other length units if the problem states otherwise. In that case, you would have to use dimensional analysis.

SimranSangha4I
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Re: Unit for Wavelength

Postby SimranSangha4I » Sun Oct 20, 2019 2:36 pm

The wavelength measures the distance between each wave! So the unit for wavelength would be in meters (m) but we also frequently use nanometers (nm). The conversion would be 1nm= 10^-9 m!

gabbymaraziti
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Re: Unit for Wavelength

Postby gabbymaraziti » Sun Oct 20, 2019 3:41 pm

The unit for wavelength is meters... but, we aren't provided the conversions to nanometers, picometers, etc. on tests, so you should memorize the conversions for these.

Tyler Angtuaco 1G
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Re: Unit for Wavelength

Postby Tyler Angtuaco 1G » Sun Oct 20, 2019 3:46 pm

In the context of light, wavelength is usually given in nano-meters.

Abigail_Hagen2G
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Re: Unit for Wavelength

Postby Abigail_Hagen2G » Sun Oct 20, 2019 3:48 pm

The general unit is meters, but it wavelength can usually be put in nanometers

lilymayek_1E
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Re: Unit for Wavelength

Postby lilymayek_1E » Sun Oct 20, 2019 5:58 pm

wavelength, as everyone said above ^ is in meters, but probably know picometers (10^-12) and nanometers (10^-9) conversions, since those are the most asked/common ways its asked for wavelength!

305376058
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Re: Unit for Wavelength

Postby 305376058 » Sun Oct 20, 2019 6:13 pm

Wavelength is a measure of distance, so it will typically be in some variation of meters (nanometers, picometers, etc.).

Anna Chen 1K
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Re: Unit for Wavelength

Postby Anna Chen 1K » Sun Oct 20, 2019 7:07 pm

The standard unit for wavelength is meters (m) but it can be converted from nanometers, centimeters, etc.

Elizabeth 4I
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Re: Unit for Wavelength

Postby Elizabeth 4I » Sun Oct 20, 2019 7:14 pm

units for wavelength are usually measured in meters or other prefixes of meters

305303255
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Joined: Thu Jul 25, 2019 12:16 am

Re: Unit for Wavelength

Postby 305303255 » Sun Oct 20, 2019 8:23 pm

The unit is meters, but can also be a variation of that like nano- and pico- meters

J Medina 2I
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Re: Unit for Wavelength

Postby J Medina 2I » Sun Oct 20, 2019 8:29 pm

Wavelengths are measured in meters since it is a distance. It is common to see them measured in nanometers which is 1x10^-9 of a meter.

Amanda Ung 4D
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Re: Unit for Wavelength

Postby Amanda Ung 4D » Sun Oct 20, 2019 8:47 pm

Wavelength is measured in meters but always keep in mind the conversions! Typically the problems that I've seen for wavelength call for answers in nanometers.

mayarivers3I
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Re: Unit for Wavelength

Postby mayarivers3I » Sun Oct 20, 2019 9:15 pm

Wavelength is a measure of distance so the unit is meters, but can be seen as pico- and nano- meters.

abby hyman
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Re: Unit for Wavelength

Postby abby hyman » Sun Oct 20, 2019 9:17 pm

since wavelength is a measure of distance it is found in meters, pm, or nm

Caitlin Ciardelli 3E
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Re: Unit for Wavelength

Postby Caitlin Ciardelli 3E » Sun Oct 20, 2019 11:22 pm

Wavelength measures the peak to peak distance, and therefore is measured in meters. It is also important to note that wavelength is not limited to peak to peak specifically, it can also refer to trough to trough.

Also remember that wavelength and frequency have an inverse relationship!


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