Define wavelength What equation is used to calculate the wavelength or frequency of a wave?

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Wavelength is the distance of 1 frequency moving ridge summit to the other and is almost normally associated with the electromagnetic spectrum.^[1] Calculating wavelength is dependent upon the information y'all are given. If you know the speed and frequency of the wave, you can employ the basic formula for wavelength. If you lot want to determine the wavelength of low-cal given the specific energy of a photon, you lot would use the energy equation. Calculating wavelength is easy as long as you know the right equation.

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   Calculate wavelength with the wavelength equation. To find the wavelength of a wave, you merely have to divide the moving ridge's speed past its frequency. The formula for calculating wavelength is: ${\displaystyle Wavelength={\frac {Wavespeed}{Frequency}}}$ . ^[2]

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   Utilise the correct units. Speed can be represented using both metric and imperial units. Y'all may see information technology as miles per 60 minutes (mph), kilometers per hour (kph), meters per 2nd (g/due south), etc. Wavelength is almost always given in metric units: nanometers, meters, millimeters, etc. Frequency is by and large expressed in Hertz (Hz) which means "per 2nd".^[3]

   • Ever proceed units consistent beyond the equation. Most calculations are done using strictly metric units. If the frequency is in kilohertz (kHz) or the moving ridge speed is in km/s you will need to convert these numbers to Hertz and g/s by multiplying by 1000 (10 kHz = x,000 Hz).

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   Plug the known quantities into the equation and solve. If yous desire to summate the wavelength of a moving ridge, then all you have to do is plug the wave's speed and moving ridge'south frequency into the equation. Dividing speed by frequency gives you lot the wavelength.^[4]

   • For example: Find the wavelength of a wave traveling at 20 m/s at a frequency of 5 Hz.

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   Use this equation to solve for speed or frequency. You can rearrange this equation and solve for speed or frequency if given wavelength. To calculate speed given frequency and wavelength, utilize ${\displaystyle v={\lambda }*{f}}$ . To calculate frequency given speed and wavelength, use ${\displaystyle f={\frac {5}{\lambda }}}$ .^[5]

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   Rearrange to solve for wavelength. Yous can rearrange the equation with algebra to solve for wavelength. If yous multiply both sides of the equation by wavelength and then divide both sides by energy, you are left with ${\displaystyle \lambda ={\frac {hc}{E}}}$ . If you know the energy of the photon, you tin can calculate its wavelength.^[vii]

   This equation can also be used to make up one's mind the maximum wavelength of lite necessary to ionize metals. Simply use the energy required for ionization and solve for the respective wavelength.

3. 3

   Plug in the known variables and solve. Once you have rearranged the equation, you tin solve for the wavelength past plugging in the variables for energy. Because the other two variables are constants, they are always the aforementioned. To solve, multiply the constants together and and then divide past the energy.^[viii]

   • For example: Find the wavelength of a photon with an energy of 2.88 10 10^-19 J.

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1. 1

   Bank check your answer past multiplying the wavelength by the frequency. If yous institute the right value for the wavelength, multiplying past the frequency should become you the moving ridge speed you lot started with. If it doesn't, check your math. If yous are using a calculator, make sure you have typed the numbers in correctly.

   • For case: What is the wavelength of a 70 Hertz sound wave traveling at 343 meters per second?
     • You lot follow the instructions to a higher place and get an answer of 4.ix meters.
     • Check your work by computing four.nine meters ten 70 Hz = 343 meters/2nd. This is the wave speed you started with, and then your answer is right.

2. 2

   Use scientific note to avoid computer rounding errors. Wavelength calculations ofttimes involve very large numbers, peculiarly if you're working with calorie-free speed. This can lead to rounding errors on your calculator. Preclude this past writing your numbers in scientific notation and double checking the significant digits.^[9]

   • For example: Lite travels through water at about 225,000,000 meters per 2nd. If the wave's frequency is 4 x 10¹⁴ Hz, what is its wavelength?

3. 3

   Exercise not change frequency when a wave enters a dissimilar medium. Many word problems involve a moving ridge that crosses the purlieus from i medium to another. A mutual fault here is calculating a new frequency for the moving ridge. In fact, the frequency of the wave remains the same when it crosses the boundary, while the wavelength and wave speed alter.^[ten]

   • For case: A light wave with frequency f, speed v, and wavelength λ crosses from air to a medium with refractive index i.5. How do these 3 values modify?

4. 4

   Bank check your units. The units you utilize volition often tell you what to do when you are solving a problem. If they exercise not make sense when you end, so check to meet if you used the right units.

   • For example, perhaps you used Joules when you lot should accept used Hertz, so you lot concluded up with the incorrect answer.

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Add together New Question

• Question

  What is the formula for wavelength?

  

  Meredith Juncker is a PhD candidate in Biochemistry and Molecular Biology at Louisiana State University Health Sciences Center. Her studies are focused on proteins and neurodegenerative diseases.

  

  Scientific Researcher

  Expert Respond

  Wavelength can exist calculated using the following formula: wavelength = wave velocity/frequency. Wavelength normally is expressed in units of meters. The symbol for wavelength is the Greek lambda λ, so λ = 5/f.

• Question

  How exercise I summate the wave length given only the frequency?

  

  Meredith Juncker is a PhD candidate in Biochemistry and Molecular Biology at Louisiana State Academy Health Sciences Center. Her studies are focused on proteins and neurodegenerative diseases.

  

  Scientific Researcher

  Adept Answer

  The speed of calorie-free never changes, and then v will always equal three.0 10 ten^8 m/due south. This value, divided past the given frequency, volition requite you wavelength.

• Question

  If the frequency of a radio wave is 4.5GHz, what is the wavelength of the moving ridge (velocity of light=3x10m/south)?

  

  Meredith Juncker is a PhD candidate in Biochemistry and Molecular Biological science at Louisiana State University Health Sciences Center. Her studies are focused on proteins and neurodegenerative diseases.

  

  Scientific Researcher

  Expert Answer

  f = 4.5 GHz = 4.5 ten ten^9 Hz (Hz = south^-i) v = 3.0 x 10^viii g/due south lambda = five/f = (iii.0 x 10^8 m/southward) / (4.5 x 20^nine due south^-one) = 0.0666 m = 66.6 um

• Question

  How practice I calculate wavelengths?

  

  If you want to calculate the wavelength of a wave, plug the wave'south speed and frequency into the equation. Dividing speed past frequency gives you the wavelength.

• Question

  What is the speed of a sound wave that is 30Hz and has a wavelength of 5M?

  

  Wavelength = 5M. Freq = 30 Hz. Speed = 5m x 30 Hz. 150 m/s is speed. See formula wavelength = speed of moving ridge / frequency.

• Question

  How practice I work out the maximum wavelength?

  

  To determine the maximum wavelength of light, you simply use the energy equation. If you know the amount of free energy required for the reaction, you plug it into the equation λ = hc/E.

• Question

  If a indicate has wavelength of 2um in air, how far can the front of the moving ridge travel during 3000 periods?

  

  A wavelength is how long a moving ridge (signal) travels over 1 period, so the calculation would be: 2µm * 3000, which equals 6000µm, or 6mm.

• Question

  A station transmits radiowaves on a frequency 600Hz. How practise I calculate the wavelength of the moving ridge?

  

  Danoyachtcapt

  Top Answerer

  The frequencies given are in the sound range, but if a radio transmitter could operate in that range, you could use the following equation: Wavelength in meters = 300,000 / frequency in kHz.

• Question

  The wavelength of the signal from radio transmitter is 200 khz. What is the wavelength from a transmitter operating at thou hz and at what speed do the radio waves travel?

  

  Danoyachtcapt

  Top Answerer

  The frequencies given are in the audio range, simply if a radio transmitter could operate in that range, yous could use the following equation: Wavelength in meters = 300,000 / frequency in khz.

• Question

  How do I calculate wavelength of a wave using a distance-deportation graph?

  

  The wavelength of moving ridge is the shortest distance that the wave begins to echo itself, or the distance between one peak the next summit. If the distance between two peaks is ii meters, and so the wavelength is ii meters.

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Article Summary X

To summate wavelength, employ the formula wavelength = speed divided past frequency. Just plug in the wave'due south speed and frequency to solve for the wavelength. Retrieve to utilize the correct units when you lot're using the formula and writing your reply. If you want to learn more than, like how to summate wavelength with the energy formula, keep reading the commodity!

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