Radioactive Definition and 391 Threads

I visited Chernobyl recently with a tourist company, having read that the radiation levels that I would be exposed to were okay for a limited amount of time. I learned on the trip however, that the greatest risk consisted in getting contaminated particles in your body. The guide took us around...

Homework Statement The number of radioactive nuclei in a particular sample decreases over a period of 26 days to one-fifteenth of the original number. What is the half-life of the radioactive material, in days? Homework Equations R=DN/Dt=(lambda)(N)=(N)(ln2/T1/2) The Attempt at a Solution...

I'm taking an introduction course for simple physics. All problems are solved with simple single variable analysis. My problem is that this is an introduction where you don't need any advanced math to solve the problems, but I can't remember how to solve the last equation. Would you mind helping...

I understand that it's possible to calculate the age of terrestial planets through radioactive dating their soil. However, the gas planets present a different challenge since we cannot currently land on them. Any ideas on how to calculate their ages in a different manner?

Hi All, http://arxiv.org/abs/1205.0205 Quite unbelievable! Anybody knows what is going on with the research of this, are the results confirmed, propositions of the cause?

I am a non physicist-scientist, but landed here searching the internet for this answer. Has it ever been done? Thank you for any answers.

1. The Problem Construct a mathematical model (system of differential equations) for a radioactive series of 3 elements. X,Y, and Z (Z is a stable element). (Note: W decays into X, X decays into Y, and Y decays into Z). At time zero there are 100e (approx. 271.828) moles of element X. After two...

Homework Statement Homework EquationsThe Attempt at a Solution i believe that a half-life of several years is too long to gather the data but i can't figure which of the 2 emitter and why? the answer is given to be C

1. The half-life of 238 92U is 4.5 × 109 years, which is much larger than all the other half-lives of the decays in the series. A rock sample when formed originally contained 3.0 × 1022 atoms of 238 92U and no 206 82Pb atoms. At any given time most of the atoms are either 238 92U or 206 82Pb...

Although it was drummed into me that electrical neutrality is preserved, I am perplexed by the phenomenon of radioactive decay. How is electrical neutrality maintained when electrons (beta particles) and proton-neutron sets (alpha particles) are being spit out by some elements. These particles...

Homework Statement Analyzing 1000 events (each event is one radioactive decay of an unknown sample), we notice that the time between two consecutive events is larger than 1 second in 30% of the cases while in 5% it is longer than 2 seconds. Can we, at 5% risk level deny the hypothesis, that the...

Homework Statement Magnesium (Z = 12) has isotopes that range from Mg–20 to Mg–31. Only Mg–24, Mg–25, and Mg–26 are not radioactive. What mode of radioactive decay would convert Mg–20, Mg–21, Mg–22, and Mg–23 into stable isotopes most quickly? (A) electron emission (B) alpha particle emission...

Homework Statement Homework Equations N= (N_0) e^(-kT) k = ln(2)/(T_1/2) The Attempt at a Solution N0 = 7.5g T_1/2 = 22.3 years T = 17.5 years k = ln(2)/22.3 = .031 N = 7.5 e^(-.031 * 17.5) N = 4.36 g So I chose A, but the correct answer was B. can't figure out where I went wrong

Homework Statement A radioactive source is to be used to produce electrical power from the alpha decay of 238 Pu (half life of 88 years). a) What is the Q value for the decay? b) Assuming 100% conversion efficiency, how much power could be obtained from the decay of 1.0 g of 238 Pu? Homework...

Hi everyone! I have two questions about radioactive decay that some of you might be able to answer (I'm a mathematician and no physicist by the way). The first one is very general: As I understand it the time at which a single instable atom decays is believed to be a truly random process. But...

I just purchased a niobium-titanium rod, that I assume was once used in an accelerator experiment. Is there any danger that it might have a hazardous degree of radioactivity, from exposure to synchrotron radiation, assuming it was on the outside curve of a particle accelerator...

Homework Statement the variation of nuclear binding energy per nucelon of nuclei P , Q , R and S are shown. Which process most likely to occur? the ans is P to Q ... why not S to R ? both P to Q and S to R involve formation of unstable nucleus to more stable nucleus... Homework...

What book do you recommend me to read to fully understand the radioactive decay law (equation, derivation, graphs, units)?

I would hope it is not unsolvable but I know I will be dead long before this mess is cleaned up and I hope that it is resolved in my grandchildren's generation. They are in their twenties now and have children of their own. All of us anti nuke people talk about solar power and other alternative...

So I came across something learning about carbon dating because new student in university taking geology. So brushing up more on fossils and obscure things so the year won't be a total shock. I inevitably got interested by what I was reading then I stumbled on the creationist blogosphere...

http://en.wikipedia.org/wiki/Schr%C3%B6dinger's_cat I don't understand, if the radioactive source is put in there then of course the Geiger counter will detect radioactivity so we know the cat must be dead?

Homework Statement Can someone check this please ? Calculate the maximum number of 116In nuclei (number in equilibrium) in the sample if the half-life of 116In is 54 m. Homework Equations The Attempt at a Solution The half life is 54 minutes, converted to seconds = 54m...

Hello! So I have an issue with determining the probability of a daughter isotope's nucleus being on a certain level after decay from an unstable parent isotope's nucleus on another level. For example: I have a Co-60 nucleus and it decays to a Ni-60 nucleus by B- emission. If the parent Co-60...

Definition/Summary Radioactive decay is the process in which an unstable atomic nucleus loses energy by emitting radiation in the form of particles or electromagnetic waves. This decay, or loss of energy, results in an atom of one type, called the parent nuclide transforming to an atom of a...

Hey Everyone, Just wondering what would be a good experimental investigation involving a radioactive source and the shielding of it. Simple ones I was thinking about were the effects of changing the distance the shield is from the source, the material of the shield and also the thickness of the...

I'm skeptical about a some things in physics as some things are hard to understand, or I need to see proof to believe it. I find that for physics, it helps a lot to see a real life demonstration (video) of what's being explained. I understand the whole radioactive decay thing, but I have not...

I have a really basic question about radioactive decay. If it takes 4.4 billion years for uranium-238 to decay into thorium-234, how can the decay rate be measured? What intermediate activity is taking place that would give an indication of the time it would take an atom to decay into the next...

Hi, I am doing a survey on existing methods of cleaning up radioactive materials for a personal project on cleanup of existing radiated sites. I have done some googling but some things still remain unclear so I'm going to ask you all on the forum. Here are the questions: 1. How are...

Hi all, I have a couple questions about radiation from radioactive elements. I've read a lot of articles on the different types of radiation given off by elements undergoing nuclear decay (alpha, beta, and gamma) but I haven't been able to answer the following question: What is the...

I would like to ask will the daughter of a decayed particle carries net charge? For example, after beta negative decay will the daughter atom carries net positive charge and in an alpha decay the daughter carries net negative charge? I search many textbooks and none of them mention about the...

Homework Statement If you have 500g of Thorium-234 at t=0. Calculate the initial activity and the activity after 2 weeks. The half life of thorium-234 is 24 days. Homework Equations A=A_0e^{-\lambda t} \\ A_0=\lambda N_0 \\ \lambda=\frac{ln2}{t_{\frac{1}{2}}} The Attempt at a Solution For the...

Homework Statement The average counting rate of a radioactive sample is 486 cpm (counts per minute). Find the probability that in any given 10s interval one gets less than 72 counts. Is this the same as the probability of getting less than 72 X 6 = 432 counts in 60s? Homework Equations...

Sorry about my poor English. I heard Jupiter emits lethal amounts of radioactivity (I don't know what kind). I also read things that suggested that there are areas where this radioactivity is more intense than on other areas. I wanted to know a few things: a) why does Jupiter emits so...

The formula for radioactive decay over time is N = N0eλt . The formula for how many number of atoms counted by the Geiger as distance (x) changes is C = k/x2. How can I merge these formulas to give one that accounts for distance and time? Secondly, how does the second formula work...

These guys made a stupid and 'fatal' mistake. http://www.washingtonpost.com/world/stolen-cobalt-60-found-in-mexico-curious-thieves-likely-doomed/2013/12/05/262ef990-5d66-11e3-8d24-31c016b976b2_story.html

Hi there, I have a few closed radioactive sources (Cs137, Pb210, Na22) that I am trying to use for a project but I am not that knowledgeable about them. Their activity is shown on the source but I'm unsure if this is related to the amount ie grams of substance inside the sealed container...

Here's a radioactive binding assay: 1. Mix radioactively labeled ligand of known concentration with normal ligand (assuming radioactivity does not affect the ability to bind). 2. Add the mixture of labeled and unlabeled ligand into the solution of receptor. 3. Separate bound ligand from...

Why c - 14 is radio active though n/p ratio is less than 1.5?

Homework Statement A certain nuclear plant produces radioactive waste in the form of strontium-90 at the constant rate of 500kg. The waste decays exponentially with a half-life of 28 years. How much of this radioactive waste from the nuclear plant will be present after the following...

I have heard that if n/p ratio of a substance becomes more than 1.56, it becomes radioactive. But for Cobalt-60, n/p= 1.22. Yet it is radioactive. Why is that so? Thanx in advance...

Homework Statement A sample of Mo-101, initially pure at time zero, beta decays to Tc-101 which then beta decays to Ru-101 (stable). The half-lives of Mo-101 and Tc-101 are nearly the same and for this problem are assumed equal (14.4 min). After a decay period of one half-life how many atoms...

Hi all, just to point out that I am a lay person as far as physics go, but thought that perhaps someone here can help me! While in St. Petersburg recently I went to a flea market and purchased the ship's compass from a Soviet Submarine. Not exactly sure from which sub or when it was built...

Homework Statement "How could you show that a radioactive source was only emitting alpha and gamma radiation?"The attempt at a solution This really stumped me...obviously they have different penetration distances, and different strengths of ionisation, but I don't know how to show that only...

Why don't they just place spent fuel rods in canisters and put them on the bottom of the ocean (at a traceable location, of course)? Water is one of the best radiation shields. You wouldn't have to worry about digging out mountain caverns and such.

Homework Statement The nuclide (32,15)P undergoes Beta - decay with a half-life of 14.3 d. It is used as a tracer isotope in biochemical analysis. What is the initial decay rate of a 1.2mg sample? Homework Equations T1/2 = Ln 2 / λ Ro = λN0 The Attempt at a Solution I first...

Hi, I was wondering how to derive relationship between radiocative constant and half life, which is t1/2=ln2/b, where b=decay constant. It seemed like the it was just replaced into the equation A=A0(1/2)t/t1/2. Thanks in advance

So I recently heard of a simple way of thinking about how the emission of an alpha particle is "beneficial" to a nucleus being stable. The argument goes as follows: "Let's say we have a nucleus that is unstable because the electric repulsion of protons can't balance out the strong force...

Radioactive decay of granite ---> How many years does it take? Homework Statement Radioactive decay of granite and other rocks in the Earth's interior provides sufficient energy to keep the interior molten, to heat lava and to provide warmth to hot springs. This is due to the average release...

Homework Statement The amount (A) of cesium-137 remaining after t years is given by A=A_{0}*2^{\frac{-t}{30.3}} where A_{0} is the initial amount. In what year will the cesium-137 be 10% of that which was released at the Chernobyl disaster in 1986? Homework Equations...

This isn't a direct question and answer problem, it relates to an essay I am doing. I am a bit confused on the equations given by my tutor for radioactive decay, I suspect there is a mix up of symbols used where two symbols are used for the same think (such as N and R for the normal force). On...