Radioactive decay Definition and 216 Threads

Alright so i have exams in a matter of days and stumbled upon this multiple choice question 7. A radioactive source has 1.6×10^20 atoms of a radioactive isotope, with a half-life of 3 days. How many atoms will decay in 12 days? A. 1.0×10^19 B. 1.2×10^20 C. 4.0×10^19 D. 1.5×10^20 So my first...

What equation would I need to use to determine the energy of photons released when radio-isotopes decay? I would like to figure out the energies of photons released when tritium and plutonium 237 decay.

Hello, Are there any anthropologists, archaeologists, or geologists around on this board for help? I am trying to teach myself about radioactive decay via beta emission whereby a neutron spontaneously transmutes into a proton, releasing an electron. But, I do not understand the practical side...

Homework Statement A radioactive material decays by simultaneous emission of two particles with respective half lives 1620 and 810 years. The time, in years, after which one-fourth of the material remains is: Homework EquationsThe Attempt at a Solution I'm confused whether the half lives...

Homework Statement Two isotopes N1, N2. You are given the value of the proportions N1(t1)/N2(t1) and N1(t2)/N2(t2). From this calculate Δt. Homework Equations dN/dt = -λN The Attempt at a Solution Solve dN1/N = -λdt and dN2/N = -λdt obtain: N1(t2) = N1(t1)exp(-λ1(t2-t1)) (1) and N2(t2) =...

Among the radioactive products emitted in the 1986 Chernobyl reactor accident were 131I ( t1/2 = 8.0 d) and 137Cs (t1/2 = 30 y). There are about five times as many 137Cs atoms as 131I atoms produced in fission. (a) Which isotope contributes the greater activity to the radiation cloud? Assume the...

Homework Statement Charred wood remains were found in Conimbriga, probably with Roman origin. When measured at 14C activity in these remnants, it afforded 10.8 disintegrations per second per gram. The half-processing 14C is 5730 ± 30 years and the activity of this isotope in the atmosphere and...

Hi guys, in my plot I have an unstable isotope of an alien element and I was wondering wouldn't it be nice if most of the particles generated from the decaying are entangled, how do you think, does it sound silly and totally impossible? If it is a good idea, then how such a property can be used...

Homework Statement Are the number of electrons on both sides of the radioactive decay balanced? Homework Equations For example, consider an alpha decay. ZPA → Z-2DA-4 + 2He4 For P, Number of Neutrons = A - Z Number of Protons = Z Number of Electrons = Z For D, Number of Neutrons = [A - 4] - [Z...

Also, How do we know the radioactive decay is constant? I know that carbon dating cannot be 100% accurate because the rate of production fluctuates based on cosmic rays hitting our upper atmosphere. Why isn't this true with Earth metal isotopes? Is time truly constant? It seems like a lot...

Hi Guys Is there a simple test by which one could determine the type of decay a radioactive specimen is undergoing? Thanks sonip

what causes radioactive decay i mean i know throw decay could turn unstable to stable atom. But what cause it unstable?

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 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 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...

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)?

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...

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...

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...

Homework Statement I am a freshman in physics, just done a lab about radioactive decay. I've measured the # of beta particles per second 400 times and got the frequency of each number K using Excel. I'm supposed to take the data and fit it to a puason distribution in MATlab. The data points...

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...

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...

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...

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...

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...

Radioactive Decay Probability? Say you are counting the number of decays and the time of observation is varied. I know that as time increases, the Gaussian Distribution becomes a closer fit to the observed probability than when the time interval takes smaller values because the mean count...

I ask this because I've heard repeatedly that all the equations in current physics models are reversible in time, save the second law of thermodynamics. But does this mean the process of radioactive decay is also reversible in time?

I would like to hear opinions on the variation in decay rates as described by Fischbach and coworkers and how (if at all) this will affect radioemtric dating. Does this phenomenon indeed exist or is it the result of errors in experimental technique?

What are the thoughts about using a magnetic sail propelled by a powerful alpha emitter (e.g. polonium)? Imagine a 1kg sphere of polonium radiating alpha particles in all directions. Attached to the sphere, via boon, is a powerful magnetic field emitter that would repulse or even deflect forward...

Homework Statement The radioactive decay of a substance is proportional to the present amount of substance at any time t. If there was 15 grams at t=0 hours and 10 grams at t=3 hours. Set up the differential equation that models this decay and use the method of separation of variables to solve...

Homework Statement Radioactive decay is: N = N0e-λt N can also be used to describe count rate after a time, (t) where N0 is intial count rate and λ is decay constant... Half life, t1/2 od radioactive isotope is t1/2 = 1n2 λ The λ should be under the ln2 but it won't let...

Homework Statement A radioactive sample contains 2.25g of an isotope with a half-life of 3.8 days. How much of the isotope in grams will remain after 11.0 days? Homework Equations The Attempt at a Solution Hi! I've just started college this semester. I'm taking Introductory Chemistry. Right...

Homework Statement The initial amount of radioactive atoms on a sample of 24Na is 10^10. It's half-life corresponds to 15 hours. Give the amount of 24Na atoms that will disintegrate in 1 day.Homework Equations I started to solve it using the formula N=Initial Amount of Atoms /...

I've just been really thrown off by what this problem is asking me. Given: The decay of a radioactive material may be modeled by assuming that the amount A(t) of material present (in grams) at time t (minutes) decays at a rate proportional to the amount present, that is dA/dt= -kA for some...

Homework Statement A sample of thorium-226 is stored in a lead box. Thorium-226 undergoes alpha decay. The lead box has a small opening on the left side to allow a stream of alpha particles to escape. In the sample a nucleus of thorium-226 is at rest when it undergoes alpha decay. The daughter...

Homework Statement A meteor contains 2.45kg of plutonium-239. It has a half-life of 24065 years. Calculate: a) The number of plutonium molecules currently present in the meteor (at. mass = 239.052) b) How long ago the meteor struck the Earth if originally it contained 10kg of plutonium...

Homework Statement 2. A meteor contains 6kg of molybdenum-93. Calculate: a) The number of molybdenum molecules currently present in the meteor. b) How long ago the meteor struck the Earth if the original amount contained 20kg of molybdenum.Homework Equations Answers: 2. a) 3.884x1022...