# Half-LifeWatch

#1
Could someone explain what a half-life is please? I don't get it.
0
9 months ago
#2
Example:
800 divide 2 = 400 (1 half life)
400 divide 2 = 200 (2 half life’s)
200 divide 2 = 100 (3 half life’s)

Understand?
0
#3
Example:
800 divide 2 = 400 (1 half life)
400 divide 2 = 200 (2 half life’s)
200 divide 2 = 100 (3 half life’s)

Understand?
Wait I think I get it its like you have to divide 800 by 2, twice, to get 200, so it would have 2 half life's
1
9 months ago
#4
(Original post by 14georgec)
Could someone explain what a half-life is please? I don't get it.
It's the amount of time for something to halve. It could be the effectiveness of a drug, or in GCSE physics, the size of a piece of radioactive material. There's a decent definition on the BBC Bitesize webpage here.
0
9 months ago
#5
It's the amount of time it takes for half of the unstable nuclei to decay.
For example if it had 4000 counts at first you measure the time it takes to fall to 2000 counts. This could be 3 years for example. And in another 3 years it will fall to 1000.
4000 to 2000 (3 years)
2000 to 1000 (another 3 years so 6 years)
1000 to 500 (another 3 years so 9 years)
0
9 months ago
#6
In physics, half life means the amount of time needed for a radioactive material to lose 50% of its mass by radiation. For example, if 1 kg of an isotope of a radioactive element (let's call it quantanium) needs 8 hours to turn into 0,5 kg of quantanium, then that isotope of quantanium has a half life of 8 hours
0
#7
(Original post by Duncan2012)
It's the amount of time for something to halve. It could be the effectiveness of a drug, or in GCSE physics, the size of a piece of radioactive material. There's a decent definition on the BBC Bitesize webpage here.
(Original post by hp4300)
It's the amount of time it takes for half of the unstable nuclei to decay.
For example if it had 4000 counts at first you measure the time it takes to fall to 2000 counts. This could be 3 years for example. And in another 3 years it will fall to 1000.
4000 to 2000 (3 years)
2000 to 1000 (another 3 years so 6 years)
1000 to 500 (another 3 years so 9 years)
(Original post by Stakanovicius)
In physics, half life means the amount of time needed for a radioactive material to lose 50% of its mass by radiation. For example, if 1 kg of an isotope of a radioactive element (let's call it quantanium) needs 8 hours to turn into 0,5 kg of quantanium, then that isotope of quantanium has a half life of 8 hours

Thank you so much xx can't emphasise how helpful youse are xx
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