how to find the speed of a wave

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Wavelength is the altitude of 1 frequency wave superlative to the other and is most commonly associated with the electromagnetic spectrum.^[one] Calculating wavelength is dependent upon the data yous are given. If you know the speed and frequency of the wave, you can utilize the bones formula for wavelength. If you want to make up one's mind the wavelength of lite given the specific free energy of a photon, you would utilise the energy equation. Calculating wavelength is easy as long as you know the correct equation.

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Calculate wavelength with the wavelength equation. To find the wavelength of a wave, you just have to divide the wave's speed past its frequency. The formula for calculating wavelength is: $Wavelength={\frac {Wavespeed}{Frequency}}$ . ^[two]
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Apply the correct units. Speed can exist represented using both metric and regal units. You lot may see information technology as miles per 60 minutes (mph), kilometers per hour (kph), meters per 2nd (m/s), etc. Wavelength is nigh always given in metric units: nanometers, meters, millimeters, etc. Frequency is generally expressed in Hertz (Hz) which means "per second".^[3]
- Always keep units consistent across the equation. Virtually calculations are washed using strictly metric units. If the frequency is in kilohertz (kHz) or the wave speed is in km/s you will need to convert these numbers to Hertz and m/s by multiplying past 1000 (10 kHz = 10,000 Hz).
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Plug the known quantities into the equation and solve. If you want to calculate the wavelength of a wave, and so all you have to do is plug the wave'due south speed and wave'southward frequency into the equation. Dividing speed by frequency gives you the wavelength.^[4]
- For example: Find the wavelength of a wave traveling at xx g/southward 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, use $v={\lambda }*{f}$ . To calculate frequency given speed and wavelength, use $f={\frac {v}{\lambda }}$ .^[5]

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Rearrange to solve for wavelength. You tin can rearrange the equation with algebra to solve for wavelength. If you multiply both sides of the equation by wavelength and then divide both sides past energy, you are left with $\lambda ={\frac {hc}{Due east}}$ . If you know the free energy of the photon, yous can summate its wavelength.^[7]

This equation tin also be used to decide the maximum wavelength of calorie-free necessary to ionize metals. Simply use the free energy required for ionization and solve for the corresponding wavelength.
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Plug in the known variables and solve. Once yous accept rearranged the equation, you tin solve for the wavelength by plugging in the variables for free energy. Because the other two variables are constants, they are always the aforementioned. To solve, multiply the constants together and and so carve up by the energy.^[viii]
- For instance: Find the wavelength of a photon with an energy of 2.88 x 10^-19 J.
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Check your reply past multiplying the wavelength past the frequency. If y'all constitute the right value for the wavelength, multiplying by the frequency should get y'all the wave speed yous started with. If it doesn't, check your math. If you are using a calculator, make sure you have typed the numbers in correctly.
- For example: What is the wavelength of a seventy Hertz sound wave traveling at 343 meters per second?
  - You follow the instructions above and get an answer of 4.9 meters.
  - Check your work by computing iv.nine meters x seventy Hz = 343 meters/2nd. This is the moving ridge speed you started with, so your respond is correct.
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Utilize scientific annotation to avoid calculator rounding errors. Wavelength calculations frequently involve very big numbers, peculiarly if you're working with calorie-free speed. This tin can lead to rounding errors on your calculator. Prevent this by writing your numbers in scientific note and double checking the significant digits.^[nine]
- For example: Light travels through water at virtually 225,000,000 meters per 2d. If the moving ridge's frequency is iv x 10¹⁴ Hz, what is its wavelength?
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Exercise not alter frequency when a moving ridge enters a dissimilar medium. Many discussion problems involve a wave that crosses the boundary from ane medium to some other. A common mistake here is calculating a new frequency for the wave. In fact, the frequency of the wave remains the aforementioned when it crosses the boundary, while the wavelength and moving ridge speed change.^[10]
- For example: A light wave with frequency f, speed v, and wavelength λ crosses from air to a medium with refractive index 1.5. How do these three values change?
4
Check your units. The units y'all apply will often tell you what to do when you are solving a problem. If they do not make sense when you cease, then check to run across if y'all used the right units.
- For example, perhaps you used Joules when yous should have used Hertz, so y'all ended up with the wrong reply.
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Question

What is the formula for wavelength?

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

Scientific Researcher

Skilful Reply

Wavelength tin be calculated using the post-obit formula: wavelength = wave velocity/frequency. Wavelength commonly is expressed in units of meters. The symbol for wavelength is the Greek lambda λ, so λ = v/f.
Question

How exercise I calculate the wave length given just the frequency?

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

The speed of lite never changes, then v will always equal 3.0 10 10^eight one thousand/south. This value, divided past the given frequency, will requite you lot wavelength.
Question

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

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

Scientific Researcher

Expert Answer

f = 4.5 GHz = 4.5 x 10^ix Hz (Hz = southward^-1) 5 = 3.0 10 10^8 thou/s lambda = five/f = (iii.0 x 10^8 g/south) / (four.5 x 20^9 due south^-i) = 0.0666 one thousand = 66.6 um
Question

How do I calculate wavelengths?

If yous desire to calculate the wavelength of a wave, plug the wave's speed and frequency into the equation. Dividing speed by frequency gives you lot the wavelength.
Question

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

Wavelength = 5M. Freq = 30 Hz. Speed = 5m 10 thirty Hz. 150 one thousand/s is speed. Encounter formula wavelength = speed of moving ridge / frequency.
Question

How do I piece of work out the maximum wavelength?

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

If a signal has wavelength of 2um in air, how far can the front end of the wave travel during 3000 periods?

A wavelength is how long a wave (indicate) travels over 1 menses, so the calculation would be: 2µm * 3000, which equals 6000µm, or 6mm.
Question

A station transmits radiowaves on a frequency 600Hz. How do I calculate the wavelength of the wave?

Danoyachtcapt

Top Answerer

The frequencies given are in the audio range, but if a radio transmitter could operate in that range, you could use the post-obit 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 1000 hz and at what speed do the radio waves travel?

Danoyachtcapt

Top Answerer

The frequencies given are in the audio range, but if a radio transmitter could operate in that range, y'all could apply the post-obit equation: Wavelength in meters = 300,000 / frequency in khz.
Question

How practice I calculate wavelength of a wave using a distance-displacement graph?

The wavelength of wave is the shortest distance that the wave begins to repeat itself, or the distance between one peak the next peak. If the distance between 2 peaks is 2 meters, and so the wavelength is ii meters.

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Article Summary X

To calculate wavelength, use the formula wavelength = speed divided by frequency. Just plug in the wave's speed and frequency to solve for the wavelength. Remember to utilize the correct units when you're using the formula and writing your answer. If you desire to learn more, like how to calculate wavelength with the free energy formula, keep reading the commodity!

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