Activity Definition and 193 Threads

Dear all, I am looking for more information how specific activity \frac{Bq}{g} and surface activity \frac{Bq}{cm^2} is measured. This is done to determine whether the materials of interest can be treated as harmless and disposed as usual waste. I am interested how the experimental procedure...

I am drowning in math right now and would love some help bc I am horrible at math. Here is what I have got. Question: 1. The four major blood groups are designated A, B, AB and O. Within each group there are two types; positive and negative. Find data on the relative frequency of these eight...

Colli Albani (Alban Hills) is located 20 km (12 mi) southeast of Rome and about 24 kilometres (15 mi) north of Anzio. It has been considered a quiescent volcanic complex - until recently. An ancient volcano on the outskirts of Rome is showing signs of another enormous eruption – some time in...

I would like to do a classroom demonstration using plaster of paris (or something similar) shells dissolving in a low pH solution, simulating ocean acidification. I would like the reaction to happen quite quickly in front of the classroom. What solution could I use to dissolve plaster of paris...

A journalist reported a 'New Earthquake Swarm is Rocking Oregon's Mt Hood. http://www.wired.com/2016/05/new-earthquake-swarm-rocking-mt-hood I wouldn't say rocking. I checked USGS, and didn't find anything over Mag 2.5, so I refined the search in the range of Mag 1 to 2.5, and found a number...

what is the formula to determine the specific activity of radionulcide in sediments

There's been some activity along the Sunda trench, the region where the Australia plate interacts with the Eurasia plate (Sunda Plate) along the southern border of Indonesia. I'm wondering if we'll see a Mag 7.0 or greater soon...

I was looking to find the volume( Rk) and surface area (Qk) parameter for an N-O bond in a pyridine N-oxide molecule?

1. Does LIGO give also any information about seizmic activity? (I think as aspect intended primary to seizmic activity, not in connection with gravitational waves.) 2. Will measurement of gravitational wave give any information about quantum gravity? Is here any plan for this usage?

Breaking News: North Korea claims it has conducted a successful hydrogen bomb test South Korea says "artificial earthquake" detected near North Korean nuclear testing site http://news.yahoo.com/earthquake-detected-north-korea-not-clear-nuke-test-020439757.html That will certainly stir...

Good evening. I recently was taught how to use our new water activity meter, and I noticed something strange. This meter uses changes in the reflectance of a mirror. Whenever we'd bring the sample up to temperature, the measurement would reach a low point, then at about 0.5° below our set...

Homework Statement what is the mass in g of the activity? (a)1μCi 241Am Homework Equations A = λN λ = ln2 / T1/2 The Attempt at a Solution A = λN 1μCi = λN N=1μCi/λ N = ( x /241 mol) × (6.022 × 1023 nuclei mol-1 ) 1μCi/λ=( x /241 mol) × (6.022 × 1023 nuclei mol-1 ) X=1μCi (241)/λ(6.022×...

The problem statement The Cobalt-60 isotope is often used in medicine. It has a half-life of 5.25 years. a) What is the activity of 1μg Cobalt in Bq (decays/second)? b) You find a sample of Cobalt that has a mass of 10 µg and has an activity of 5.0MBq. How old is that sample? This problem was...

Overall this Solar Max has been pretty disappointing. But occasionally the Sun as shown brief bursts of good activity over the last week, and for a few more days, there has been a large sunspot group traversing the solar face. AR2403 is a massive spot group and one of the largest this solar max...

According to my chemistry textbook, Cu will not be oxidized by Pb(NO3)2, for Cu is lower on the activity series relative to Pb; Cu will not react with Pb(NO3)2. Why is that? Copper should still be able to oxidize regardless of its position on the activity series. So, why does its position on...

I'm doing high school physics and if a question says something like: A radioactive source gives count rate of 110 counts per second Can you say that the ACTIVITY is also 110 bq? My second question is how would a gieger counter detect gamma radiation? It is the least ionising of all three...

Can anyone please guide me how to find solution of this problem A 0.2-g sample of 85Kr gas, which decays into stable 85Rb, is accidentally broken and escapes inside a sealed warehouse measuring 40×30×20 m. What is the specific activity of the air inside?

I will do an experiment with a radiotracer,99Tc. The detector is NaI 1"*1". But I don't know how much of the radiotracer is nedded?

Homework Statement A sample consists of 2g of a radioactive element. The molar mass of the element is 67g. If the half life of the element is 78 hours, the activity of the sample after 48 hours is ?Homework EquationsThe Attempt at a Solution d(N)/dt = -λN (2/67 x 6.02x10^23) (ln 2 )/ (78x...

Homework Statement The element rubidium consists of two isotopes, the stable 85Rb and radioactive 87Rb (abundance 27.83%). What is the specific activity of natural rubidium chloride? Use Ar85.47 gmol-1 for rubidium element, Ar 86.91 gmol-1 for 87Rb, and Mr 120.92 gmol-1 for RbCl. Homework...

here's some awesome eruption video from the 4 Sept 2014 http://vimeo.com/105365343 cheers Dave

A region of Venezuela has a high incidence of recurrent thunderstorm activity. It is apparently a unique set of conditions - a lake surrounded by mountains, where winds blow in from the ocean, and the warm moist air combined with moisture from evaporation from the lake interacts with cooler...

What the title states. Is it possible? I can't seem to find a way (at least, from the massive stash of PDF files I downloaded about VLE/EOS) on how to employ NRTL activity coefficients with the Soave-Redlich-Kwong EOS. In other words, is there a way to get the activity coefficient models like...

I need to extend this activity somehow, but I forgot this stuff already? I learned this a long time ago, I think this activity is too simple so can someone tell me how to find the foci, assymptotes, etc, and what the "point a" is for...

Hi all, how can I find the activity of isotope which it has in area given value mCi or mR or Rem value of this? ionization energy of isotope how many distance can it travel on air and in earth-ground when I know only the Curi or Rem or Roengen? ex. Who they calculate 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...

(disregard my improvised science lingo) so like... a radio wave has a rather macroscopic wavelength. the photon is depicted as traveling back and forth in unison with the wavelength. I am having trouble understanding why the photon can't hit you from the "side". if the photon is traveling a...

"Optical activity is the tendency of chiral molecules to rotate ppl" how does a chiral molecule rotate light? Is it because of interaction of electric fields? Anyone please help me? I just need to know how a molecule physically does that?

Hello, I'm a dietetics student, and my course is really unclear about gluconeogenesis regulation, and exactly WHEN it happens. What my coursebook teaches me is that glycogenolysis is the main purveyor of energy during physical exercise, and it is triggered by LOW INSULIN, HIGH GLUCAGON and...

Hello everybody, I'm new here and i have a question about the activity of our galaxy's Supermassive Black Hole. Did it influence the star-formation activity or was it vice versa? I would be grateful if someone could tell me anything about this or give me some information directions. Thank you.

Let's say I have a general phase transition S (phase 1) ::equil:: S (phase 2). At a certain point in pressure and temperature for each phase (they can have different pressures and temperatures, we might say P1 and T1 for phase 1 and P2 and T2 for phase 2), how might we express the forward and...

I am given with the activity of alpha particle.How could i calculate its energy from it?

Homework Statement 1) What would you expect the Carbon-14 activity (in counts/minute) to be for a 1.0g sample of Carbon from a 4000-year-old Bristle pine cone? 2) What would you expect the Carbon-14 in counts/minute to be for a 20g sample of carbon from a 10000 year old fireplace found in...

Hi, I am a newbie trying out astronomy after two decades of politics, but I was hoping if someone could help translate the following statement for me (I am not a student, so your not answering an essay question or anything); We report unusual auroral features observed by the DMSP-F6...

Hi all, my end of year Physics exam is tomorrow and I need some help on this question and if someone could help I'd appreciate it. Carbon-14 has a half life of 5730 years, and an equilibrium concentration in the Earth’s lower atmosphere of approximately one atom per 8.3 x 1011 atoms of normal...

Homework Statement A natural lithium target 3.8 mg cm-2 thick is bombarded with a 125 µA beam of 3.5 MeV protons initiating a 7Li(p,n) reaction. Assuming a reaction cross section of 300 mb, calculate the activity produced by a 15 minute bombardment. Homework Equations...

Since the redistribution of mass in the Earth's surface can be caused by earthquakes, sometimes the Earth's rotation is increased or decreased by a small amount. Recent series of quakes seem to be related. To me, this makes sense, since if plate "A" should move, then plate "B" would also...

Homework Statement Radioactive nuclei A are produced at a rate R per second in a nuclear reactor. They decay with probability λ per second. (Qu 1-2 involving deriving the rate of change and number particles at any given time, I've done this). 3) Show the activity tends to R, a constant, as...

Fun physics activity! Homework Statement Under the conditions of normal activity an adult inhales about 1.1l of air during each inhalation. Using a stopwtch, determien the time for one of your own inhalations (avg several to get two significant digits) and hence estimate the volume flow in...

Hey everyone, I need help with this question: Homework Statement 2-pentanone is an important industrial intermediate. When using the pure liquid as the reference state, in which solvents (examples and explanations) would you expect it to have an activity of a) less than one, b) one...

Hello, Can Someone help me with this activity - http://www.particleadventure.org/other/education/five_s.html - its activity 5 The rules of the Game The answer to the activity is - http://www.particleadventure.org/other/education/five_s.html I don't understand how they got the answer for...

I'm curious to know how much energy a brain will use depending on the different activities it's doing. Sleeping vs. watching TV vs. doing rigorous physics problems vs. running a marathon For the above activities, what are the different energy requirements like? How do the things...

Seismic Activity Project! Please help me! So, I have to find the location of the epicenter of seismic activity. Of course, our project does not intend to find that of real seismic activity. This is a school project, in which my teacher will drop an object at some unknown location in a large...

Hi, I'm looking for a general solar activity chart that covers as much history as possible (up to this month or even better today). In a nutshell, I am looking to validate if we are in fact in a period of increasing solar activity which would apparently keep increasing until next year ...

Homework Statement The issue I have is that I am asked to estimate the activity of a small source of gamma radiation; the question is written below: 'A small source of gamma radiation is placed at a distance of 160mm from a detector of area 18mm^2. The count recorded on the detector after 30...

hi, can someone help me in understanding the difference between chemical potential and activity? Why it is important to know/determine activities of certain species in material growth? Given that activity is dimensionless quantity, what is it measuring? Also, what is the activity of pure...

According to my textbook, the decay constant is the probability that a radionuclide will decay in any second (hence the unit s^-1) and so the total number of radionuclides decaying at any second, i.e. the activity, is λN but this is also the rate of change of N thus dN/dt = -λN Surely...

Homework Statement Suppose we have done a conservation of momentum lab the smart pulley apparatus shown in the figure provided. With this apparatus we can time the motion of cart #1 very accurately. In the beginning cart #2 was stationary. We set cart #1 in motion by giving it a slight push...

the electrical activity of an atom is the same electricity of a light bulb?

The measured pH of 0.100 M HCl at 25°C is 1.092. From this information, calculate the activity coefficient of H+. I tried using the Debye-Huckel equation and got 0.825 but it's not right. I don't know how else to solve for the activity coefficient.