Radiation and nuclear energy

In summary: How are the energy and frequency of a quantum (aka "a photon") of EM radiation related?The energy of a quantum is related to its frequency. The higher the frequency, the more energy the quantum has.
  • #1
dagg3r
67
0
1. Calculate the wavelength of an x-ray which has a frequency of 10^16 Hz

2. Calculate the Energy associated with an x-ray with a frequency from Question 1.

* I don't know how to do this, but from looking at the electromagnetic spectrum, it tells you. But i want to know how to calculate it.

-------------------------------

A radioactive source (with a half life of 5 days) has an initial activity of 4000 counts/min.
3. Determine the activity after 10 days
4. If the initial quantitiy of radioactive material is 200gms, determine the amount left after 15 days have elapsed.
5. Convert 4000 counts per min into Bq's

* I know on half-life, the amount of is halved, but the activity is 4000 counts/min. so i divided 4000/60 = hrs, then divide by 24 to give days, then divide by 10 to give 10 days. but the half life is 5 days so not really sure what to do, someone can please show me how to do question 3,4,5
 
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  • #2
dagg3r,

This looks suspiciously like your homework. We don't mind helping people with their homework (we have a whole forum devoted to Homework Help. The moderator is a hell of a guy, by the way. ). However, we typically like to see how you started and where you got stuck. I will ask you to answer some questions that will help you.

Originally posted by dagg3r
1. Calculate the wavelength of an x-ray which has a frequency of 10^16 Hz

*At what speed to x-rays travel?
*How are the wavelength, frequency and speed related?

2. Calculate the Energy associated with an x-ray with a frequency from Question 1.

*How are the energy and frequency of a quantum (aka "a photon") of EM radiation related?

* I don't know how to do this, but from looking at the electromagnetic spectrum, it tells you. But i want to know how to calculate it.

No, you do not need to look at the spectrum. You have everything you need here, except two universal constants which you must look up.

A radioactive source (with a half life of 5 days) has an initial activity of 4000 counts/min.
3. Determine the activity after 10 days
4. If the initial quantitiy of radioactive material is 200gms, determine the amount left after 15 days have elapsed.
5. Convert 4000 counts per min into Bq's

* I know on half-life, the amount of is halved, but the activity is 4000 counts/min. so i divided 4000/60 = hrs, then divide by 24 to give days, then divide by 10 to give 10 days.

Why did you divide by 60 hours?

but the half life is 4 days so not really sure what to do, someone can please show me how to do question 3,4,5

10 days=2 half lives
15 days=3 half lives

That's all I'm going to say for now. Give this a try and if you are still stuck, post what you've done and we'll take it from there.
 
  • #3
Quote:
*At what speed to x-rays travel?
x-rays travel at the speed of light, All electromagnetic radiation travels at the speed of light in a vacumn i think.

*How are the wavelength, frequency and speed related?
well wavelength is the variation in colour or shade is caused by light. I think it is the combinatoin of an electric field and a magnetic field.

i think the energy and frequency of EM radiation is the same? but anyways how do i calclate the wavelength of an x-ray which as a frequency of 10^16 hz. since i know the speed of light is 3 * 10^8.
----
ok since you have told me, since 5 days is 1 halflife, 10 days is 2 halflives which i alread knew. i have to find the activity after 10 days since the initial activity is 4000 counts per minute. I'm guessint i just do 4000/2 = 2000 counts per min?

for q5 where it says initial quantitiy of material is 200gms, determine the amount left after 15 days have elasped.
i got 200/8 = 25gms, not sure if that is right...

how do i convert 4000 counts per min into bq's?
 
  • #4
I am with Tom, this sounds like homework to me also.

consider this

speed has units of m/s

wavelength is measured in meters (m)

Frequency has units of Hertz or (1/s)

Can you see a relationship between these quanities by considering their units? Remember that any algebraic relationship between physical quanties must be reflected in the dimensions (units) of the physical quanities.
 
  • #5
Originally posted by dagg3r
Quote:
*At what speed to x-rays travel?
x-rays travel at the speed of light, All electromagnetic radiation travels at the speed of light in a vacumn i think.

Right.

*How are the wavelength, frequency and speed related?
well wavelength is the variation in colour or shade is caused by light. I think it is the combinatoin of an electric field and a magnetic field.

No, it is much more basic than that. Look in your book in the chapter on electromagnetic waves, or even mechanical waves. You should have learned this some time ago.

i think the energy and frequency of EM radiation is the same? but anyways how do i calclate the wavelength of an x-ray which as a frequency of 10^16 hz. since i know the speed of light is 3 * 10^8.
----

You'll need the formula I referred to above.
 
  • #6
Use algebra before plugging in numbers. ;)
velocity = wavelength*frequency

Energy of photon=nhfrequency
n=integer

for radioactive particles
N = Noe-kt
where N = no. particles final, No = no. particles initial, k = decay constant, t = time.
 

1. What is radiation and how does it differ from nuclear energy?

Radiation is energy that is emitted from a source and travels through space or material. Nuclear energy, on the other hand, is the energy that is released from the splitting or combining of atoms in a nuclear reaction.

2. What are the sources of radiation and nuclear energy?

Radiation can come from natural sources such as the sun, soil, rocks, and even our own bodies. Nuclear energy is mainly derived from the splitting of uranium atoms in nuclear power plants.

3. Is exposure to radiation dangerous?

Exposure to high levels of radiation can be harmful to living organisms, but it is important to note that we are exposed to low levels of radiation in our everyday lives and our bodies have natural defenses against it.

4. What are the benefits of using nuclear energy?

Nuclear energy is a reliable and efficient source of energy that does not produce greenhouse gases or contribute to air pollution. It also has a high energy density, meaning it can produce a lot of energy from a small amount of fuel.

5. What are the risks of using nuclear energy?

The main risk associated with nuclear energy is the potential for accidents, such as meltdowns or leaks, which can have serious consequences for both human health and the environment. Proper safety measures and regulations are necessary to minimize these risks.

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