Radioactivity Definition and 113 Threads

You are told that potassium 44 has a half life of 20 minutes and decays to form calcium 14. Q1. how many atoms would there be in a 10mg sample of potassium? Answer: I used avogadro's constant to find this by: (6E23/44)*10E-3 = 1.4E20 atoms Q2. what would be the activity of the sample...

First off I am sorry for asking this question , as I am sure I am way off base. I collect high end pocket knives and some of the blades have become a little magnetized; so i found a demagnetizer that uses NdFeB30 magnets, which are rare earth? MY question is this, if i rub the demagnetiser over...

Till now i have not found any decent site/article/book that actually answers my question of why certain atoms such as Uranium 235/238 and carbon-14 break up spontaneously while others are relatively stable. Could someone perhaps suggest a book or website or article that explains this (i am...

Hello, anyone know a website to find the background rate of Cesium?

is radioactivity decay reversible or irreversible?

I've been reading about radioactivity, but I can't seem to find what actually makes an atom unstable. Can anyone tell me?

What is it about the density of a substance that makes it more resistant to allowing radioactivity to pass through it? Since most of the atom is empty space?

Strange radioactivity question. please help fast! I know this is in the k-12 forum too but i wasnt sure if this is college level stuff or not so sorrie if this is in the wrong forum. And I am not telling u to do this for me, i just want to know some equations and anything that wuld help...

Strange radioactivity question. please help fast! well, this is a strange question that i have to do a presentation on. I thought it would be easy but i can't find any information after looking through 2 major physics books and searching online. I even asked a tutor about this and still...

well, this is a strange question that i have to do a presentation on. I thought it would be easy but i can't find any information after looking through 2 major physics books and searching online. I even asked a tutor about this and still couldn't get any equations i could use. Plz don't bash me...

What makes nuclei disintegrate at a certain point in time as opposed to another? As in, what is the fundamental reason for disintegration finally happening in an unstable nucleus?

This may be a dumb question: What is it about radioactivity that caused them to name it "radioactive"? All I was taught was that radioactivity is an emission of gamma particles, beta particles, or alpha particles. I don't remember anything about radio wavelength photons.

a radioactive with a half-life of 5 days, has an initial activity of 4000 counts/min determine the activity after 10 days well because 1 half life is 5 days, so 10 days must be 2 so 4000/(2^2) =1000 counts/min is that right? 2. If the initial quantitiy of radioactive material is...