A college student recently had a busy day. Each of the student’s activities on that day (reading, getting a dental x-ray, making popcorn in a microwave oven, and acquiring a suntan) involved radiation from a different part of the electromagnetic spectrum. Complete the following table and match each type of radiation to the appropriate event:
I was wondering if anyone could walk me through either the steps or the formulas I am supposed to use for this problem. Thanks in advance!
Textbook Problem 1A9
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Re: Textbook Problem 1A9
IsabelMurillo3J wrote:A college student recently had a busy day. Each of the student’s activities on that day (reading, getting a dental x-ray, making popcorn in a microwave oven, and acquiring a suntan) involved radiation from a different part of the electromagnetic spectrum. Complete the following table and match each type of radiation to the appropriate event:
I was wondering if anyone could walk me through either the steps or the formulas I am supposed to use for this problem. Thanks in advance!
So I haven't done this problem yet, but I assume it is as following
Table includes frequency, wavenlength, energy of photon, and event
Energy of Photon = E = vh
Wavelength = lamda = c/v
Frequency = c/lamda or E/h
If you're given frequency -> calculate wavelength (c/v), and energy (vh)
If you're given wavelength -> calculate frequency (c/lamda), and energy by using frequency
Event would be based upon the different wavelengths
Reading - Visible Light
X Ray - X ray
Popcorn - Microwave
Suntan - UV
And match the events to the wavelengths
Ex: if wavelength is 600nm -> reading a book bc it's within visible light spectrum
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Re: Textbook Problem 1A9
Hi! For this question since they give you either the frequency, wavelength, or energy for each event, you can use the formulas E = hv and c = λv to complete the table. For example in the first line, they give the frequency, so you would use c= λv to find the wavelength and E = hv to find the energy of the photon. Then in order to match each type of radiation to each event, you could look at the wavelengths and match it to the corresponding radiation. For example, getting a suntan exposes you to UV radiation so you can match the wavelength you calculated to that of UV radiation.
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Re: Textbook Problem 1A9
I will try and give a decent explanation on how to solve this problem.
The first step of is to analyze exactly what electromagnetic waves this college student would be running in to throughout the day.
When reading, the student encounters visible light waves
When at the dentist, X-rays
When microwaving popcorn, microwaves
When at tanning, UV Rays.
The next step would be to look at the chart 1A.1.
This chart has the wavelengths, frequencies, and energies of all of the waves on the spectrum.
You would then cross-reference the values given with the corresponding wave's values.
For instance, 3.3 x 10^-19 J would be in the visible light spectrum, letting us know that while reading, he encountered that many joules.
In the end,
3.3 x 10^-19 J would be for reading
300 MHz would be for microwaves
2.5 nm would be for the dentist
8.7 x 10^14 Hz would be for UV rays.
Hope that helped!
The first step of is to analyze exactly what electromagnetic waves this college student would be running in to throughout the day.
When reading, the student encounters visible light waves
When at the dentist, X-rays
When microwaving popcorn, microwaves
When at tanning, UV Rays.
The next step would be to look at the chart 1A.1.
This chart has the wavelengths, frequencies, and energies of all of the waves on the spectrum.
You would then cross-reference the values given with the corresponding wave's values.
For instance, 3.3 x 10^-19 J would be in the visible light spectrum, letting us know that while reading, he encountered that many joules.
In the end,
3.3 x 10^-19 J would be for reading
300 MHz would be for microwaves
2.5 nm would be for the dentist
8.7 x 10^14 Hz would be for UV rays.
Hope that helped!
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Re: Textbook Problem 1A9
Hey Isabel! There are actually only two formulas you need to complete this problem so it's not too complicated once you get them.
-The first formula is the formula for wavelength. The formula is wavelength = (c (speed of light)) / (v (frequency)). Just a note, the speed of light is equal to
3.00 x 10^8 m.s^-1. This formula can be rearranged to solve for wavelength if given frequency or frequency if given wavelength.
-The second formula is the formula for energy. The formula is E (energy) = (h (Planck's constant)) x (v (frequency)). Just a note, Planck's constant is equal to
6.63 x 10^-34 J.s. This formula is used to solve for energy using frequency.
-One last hint for this problem is to make sure you check the units. One of the frequencies is given in MHz, but you need to covert it to Hz before you plug it into an equation. Similarly, one of the wavelengths is given in nanometers, but you need to convert it to meters before plugging it into an equation.
Hope this helps!
-The first formula is the formula for wavelength. The formula is wavelength = (c (speed of light)) / (v (frequency)). Just a note, the speed of light is equal to
3.00 x 10^8 m.s^-1. This formula can be rearranged to solve for wavelength if given frequency or frequency if given wavelength.
-The second formula is the formula for energy. The formula is E (energy) = (h (Planck's constant)) x (v (frequency)). Just a note, Planck's constant is equal to
6.63 x 10^-34 J.s. This formula is used to solve for energy using frequency.
-One last hint for this problem is to make sure you check the units. One of the frequencies is given in MHz, but you need to covert it to Hz before you plug it into an equation. Similarly, one of the wavelengths is given in nanometers, but you need to convert it to meters before plugging it into an equation.
Hope this helps!
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