i'm sorry but this guy is better then free science lessons. I learn so well from cognito like fully he is so easy to understand. He might actually save my GCSE grade!! I hope this video does me well for Wednesday's mock. (update: he did save my gcse and now i am in the sixth form i wanted to go to :) )
@@freyaa1200 i did terribly on physics because it was all the waves topic which was the one topic i didn't revise but it's okay i'll make up for it in biology and chemistry i hope. good luck for the paper you probably just sat :)
@@isabellaaslam9372 omg ahhh unlucky! mine was on all of the equations that we had to learn involving kWh, forces, solar panels efficiency and radiation but i didn't enjoy it at alllll hah it wasn't terrible but it was the stuff i revised the least :( thanks tho! i'm sure your chem and bio will be great! - i defo prefer these hha i've got maths non calc and spanish tomorrow, good luck on yours and i hope you have a lovely weekend :) x
If you’d like to practise what's covered in this video, check out the lesson on the Cognito platform - cognitoedu.org/coursesubtopic/p2-gcse-aqa-h-t_8.05. The platform’s totally free, and has been built to make learning and revision as easy as possible. The main features are: - Lessons organised by topic, only the lessons relevant to your specific exam board and tier are shown. - Automatic progress tracking. Progress bars tell you what you’re doing well at, and what you need to spend some time on. - Practise quizzes so you can test your knowledge. You can quiz yourself on any combination of topics you like. - A huge number of fully-hinted questions that take you step-by-step through some of the trickiest calculations & concepts. - A comprehensive bank of past exam papers, organised both by year, and also by topic. Amadeus & Tom
This guy is much more talented than my physics teacher..If I hadn't watched it on the first place,maybe it would take me a week to understand this concept...mister your knowledge is appreciated 👍💞
just learnt this today in class, was super confused but now it’s all clear thanks to you🙏👏 Edit: so it’s been 3 years lmao and i dunno why I’m updating this but I just wanted to thank this channel cuz I got A* in all my sciences:) I’m in uni now and yea thx for helping us out
I have end of years exams around these topics and you were a great help to help me revise . I don’t know where I would be in revision without this channel , you just earned another subscriber
This video legit saved my life. I learnt this about 2-3 weeks ago in class and never understood, here I am today one night before my test and I get everything. Bro you're gonna save my GCSEs.
Great video thank you I like to watch your videos one at a time every so often. Rounds my knowledge so that hopefully I’ll have good overall knowledge when it comes to my mocks and GCSEs
Hey, thank you for taking the time to leave us a comment! We really appreciate it! That’s a great strategy - little and often will get you well prepared! Good luck with all your work! 🤙
Thank you, I was really struggling with understanding half- lives and watched many videos to try help me with it but they didn't help. Now I understand, thanks!
I am new immigrants to UK,just join year 11,as my English not really good,I try very hard to listen to English,and work hard in science,thanks a lot,I learn many from this channel,but if there have subtitle,that will be perfect
you explain everything in such a clear way. this is the 3rd video i have watched about this subject and this is the first video that has actually helped me understand it thank you!!!
OMG IVE BEEN STRUGGLING WITH THIS TOPIC FOR AGES IT JUST DIDNT MAKE SENSE AND THIS GUY JUST PRASED IT IN A WAY I JUST GOT IN 10 SECONDS I LOVE THIS MAN
@@chloex971 I randomly wanted to learn about radioactive decay because of the Chernobyl series and also because of Fukishima and this video was really helpful.
Cognito is best to explain i always see your video and understand i have a book that i made... it is written cognito understanding book 😂 which i always study from that book i made my self its easy for me in exams ❤😊 that i always use
So, if I had 1kg of a radioactive substance, and its activity was, say, 30Bq. If I had 20kg of it, would the activity be the same, or would it multiply by 20?
Hi everyone, Could you please help me with this following question Radioactive materials are considered to be relatively safe when their activity has fallen below 0.1% of their initial value. (a) How much half-lives does this take? (Answer = 10 half-lives) (b) Plutonium-239 is a by product of nuclear reactors. Its half-life is 24 000 years. How long does the plutonium-239 have to be stored as nuclear waste before it is considered safe to handle? (Answer - 240 000 years)
In the question at the end, I did (5/40) x 3,000,000 Which equalled the same answer, 375,000. I don't know how my brain saw this as logic or how I did that but is this method also correct??
If anyone is wondering, the formula for calculating half life is c * 0.5^t c is the original amount (here 3000000) t is the amount of half lives (here 3) An you get the amount after 3 half lives You're welcome 🙂
Ok, can someone explain this to me? I just cant figure it out. If there were an istoped with a half life of one year and you possessed 2 samples of it. Sample A) 10lb and sample B) 1lb. After one year would you have 5lb of A and 1/2 of B? If so then it would seem that the decay rate isn't the same. Bc you managed to decay 5lb in one year in sample A but in sample B only 1/2 pould decayed after 1 year. What am I missing?
Hello, idk if you already got an answer to this since it's been 2 months. The thing is that since the atmos have a certain chance of decaying after a certain time, see it like this. Every second, each unstable atom throws a dice, if it lands on 1, it decays into a stable atom, if it lands on any other number, then it will continue being unstable. So, every second, each atom has a chance of decaying of 1 in 6. That means that after the first second we'd expect a sixth of our original sample to become some other element, so we're left with 5/6 of what we began with, if we had 36 atoms at first, we would now have 30, we lost 6 atoms. Then, after the next second, it's not going to be reduced by 6 again, now we're working with 30 unstable atoms, and since a sixth of them decay, we would now be left with 25, which is 5 less. Of course, in real life the chances are not a sixth every second. But with this example it's noticeable that decay is proportional to the sample, SO it's never a fixed amount. In your example it's first a 10lb sample and a 1lb sample, they decay into 5lb and 1/2 lb. In total it went from 11lb to 5.5 lb, proportion of decay stays the same.
@Cognito Hi!!! I was wondering if it would be possible to figure out how long it would take for something to reach ONE radioactive nucleus I have a sample of 80 trillion and a half life of 30 years!! (Chernobyl and cesium137) so would the formula of 80 trillion/2^(x/264115) = 1 and solve for x work, giving me the time it would take in hours?
Our teacher gave us a somewhat the same question but the problem is that i got 9,475.2488733336 when I divided the days from the half-life. Soooo, does that mean that I need to halve the 3.2x10^15 that many times. *sigh 😔* Hmmm I think I'll have to recheck it. O my gosh, Since the video's example says 5days, I accidentally tried to solve mine using 5days as a given when the real given states only an hour.
@@seowyy No one is more deserving of a rest... and all the effort in the world would have gone to waste until... well, let's just say your hour has... come again.
@@electroblastz The right man in the wrong place can make all the difference … in the world. So, wake up, Mister Freeman. Wake up and … smell the ashes.
this guy taught me more in 6 minutes than my physics teacher can in a week
*ever
@@AS-rq6tr aha tru :))
My physics teacher is shit
im sure you didnt learn how to make gravity gun from ur physic teacher
fr fr ;)
Alright, this guy is too underrated!! Push him to the top please, he deserves it!
yeaaa
i'm sorry but this guy is better then free science lessons. I learn so well from cognito like fully he is so easy to understand. He might actually save my GCSE grade!! I hope this video does me well for Wednesday's mock.
(update: he did save my gcse and now i am in the sixth form i wanted to go to :) )
hope it went okay! i have mine in the afternoon 🥴🥴
@@freyaa1200 i did terribly on physics because it was all the waves topic which was the one topic i didn't revise but it's okay i'll make up for it in biology and chemistry i hope. good luck for the paper you probably just sat :)
@@isabellaaslam9372 omg ahhh unlucky! mine was on all of the equations that we had to learn involving kWh, forces, solar panels efficiency and radiation but i didn't enjoy it at alllll hah it wasn't terrible but it was the stuff i revised the least :( thanks tho!
i'm sure your chem and bio will be great! - i defo prefer these hha
i've got maths non calc and spanish tomorrow, good luck on yours and i hope you have a lovely weekend :) x
@@freyaa1200 thank you! good luck and have a lovely weekend too :)
@@isabellaaslam9372 tyyyy xx
If you’d like to practise what's covered in this video, check out the lesson on the Cognito platform - cognitoedu.org/coursesubtopic/p2-gcse-aqa-h-t_8.05. The platform’s totally free, and has been built to make learning and revision as easy as possible. The main features are:
- Lessons organised by topic, only the lessons relevant to your specific exam board and tier are shown.
- Automatic progress tracking. Progress bars tell you what you’re doing well at, and what you need to spend some time on.
- Practise quizzes so you can test your knowledge. You can quiz yourself on any combination of topics you like.
- A huge number of fully-hinted questions that take you step-by-step through some of the trickiest calculations & concepts.
- A comprehensive bank of past exam papers, organised both by year, and also by topic.
Amadeus & Tom
its gotten to a point where people need to specify which half life they're talking about
@@dauzlee2827 YES HAHAHA!!!! WHICH ONE IS HE TALKING ABOUT!!!!???????
Like the game
That’s a good thing
Noice one
@R_of_L Productions frrrr
Personally, I prefer the game.
Ye
Which one
I knew someone would say this 😂
i kept thinking this during physics lmao
Half-life Alyx on top 🔥🔥
This guy is much more talented than my physics teacher..If I hadn't watched it on the first place,maybe it would take me a week to understand this concept...mister your knowledge is appreciated 👍💞
Where’s the funny screaming scientists and silly Star Wars lookin aliens?
Gordon doesn’t need to hear all this. He’s a highly trained professional!
just learnt this today in class, was super confused but now it’s all clear thanks to you🙏👏
Edit: so it’s been 3 years lmao and i dunno why I’m updating this but I just wanted to thank this channel cuz I got A* in all my sciences:) I’m in uni now and yea thx for helping us out
Aha thanks Lily - really happy it made sense to you!
@@Cognitoedu agree
Same here
@@lil_thiccpeach9067 what major are you doing
i’m so proud of you!!!
Gordon doesn't need to hear all this, he's a highly trained professional
honestly these videos are a lifesaver. And thats the biggest understatement!! Love your channel
I have end of years exams around these topics and you were a great help to help me revise . I don’t know where I would be in revision without this channel , you just earned another subscriber
This video legit saved my life. I learnt this about 2-3 weeks ago in class and never understood, here I am today one night before my test and I get everything. Bro you're gonna save my GCSEs.
Great video thank you I like to watch your videos one at a time every so often. Rounds my knowledge so that hopefully I’ll have good overall knowledge when it comes to my mocks and GCSEs
Hey, thank you for taking the time to leave us a comment! We really appreciate it! That’s a great strategy - little and often will get you well prepared! Good luck with all your work! 🤙
Rise and shine Mr. Freeman... Rise and shine...
Thank you, I was really struggling with understanding half- lives and watched many videos to try help me with it but they didn't help. Now I understand, thanks!
I am new immigrants to UK,just join year 11,as my English not really good,I try very hard to listen to English,and work hard in science,thanks a lot,I learn many from this channel,but if there have subtitle,that will be perfect
good luck i wish you all the best!
Hope your exams went well!
Youre videos are SOO helpful, i have no idea how u're not on a million subs yet. Keep up the good work 😉
All i can image is a scientist escaping a facility called black mesa
"where headcrab?" - some kid
doctor freeeeemaaaan
wait... this isnt half life 1 walkthrough (No commentry) :(
"Silly Valve, It's not 'One, two, Alyx.' it's one, two, thirty-five!"
Ha! Funny
you explain everything in such a clear way. this is the 3rd video i have watched about this subject and this is the first video that has actually helped me understand it thank you!!!
rise and shine, mr freeman, rise and shine....
How does the gravity gun work
This is the only channel that I've actually turned on the notifications of!! Just understood this topic after my physics lesson this week!
You're literally the best teacher I have. Love your videos :)
Thanks Noah, really appreciate it 😊
OMG IVE BEEN STRUGGLING WITH THIS TOPIC FOR AGES IT JUST DIDNT MAKE SENSE AND THIS GUY JUST PRASED IT IN A WAY I JUST GOT IN 10 SECONDS I LOVE THIS MAN
bro wow i have an test tomorrow on this so thanks a lot
I finally understand how to calculate half line on a graph ,thank you
This really helped man god bless you fr
You’re welcome, good luck with all your work :)
this videos are so brilliant and clear - so easy to understand! deserve so many more subscribers, these videos are such a help.
Hey thanks for such a kind comment! Really happy to hear you’re finding them useful 🙌
Great video! I actually calculated the answer correctly at the end to my surprise. I ❤️ science!
same!
@@chloex971 I randomly wanted to learn about radioactive decay because of the Chernobyl series and also because of Fukishima and this video was really helpful.
You are amazing, I finally understand this properly now.
Aha that’s greats to hear! Thanks for your support and good luck with all your work!
Thank you so much! Really helped to understand :))
Seriously helpful, thank you
for the last question u can just do 3,000,000 divide by 40 multiplied by 5 for a shorter method
Very helpful and easy to learn!
Thank you very much for the excellent explanation.
who else came to see if it's a video about the half life game?
3:09 those isotopes are REALLY distracting, it held my focus for a long time.
Great video though, helped alot :D
So helpful
🤝thank you my friend
Nice work😎
How do you calculate a half life? Also thanks this video was very helpful!!
Becky Hiskyas Just look at the graph and find the time taken for half the nuclei to decay.
Thank you for the clear explanation. How do we calculate when the decay constant is given?
Thank you so much 👏
I never thought i would use cognito for things other than... you know... (nope you naughty naughty) eductaional purpose. Thank you Cognito so much.
What an awesome video
With perfect explanation
Thank you.
thank you
plz prepare the lesson for tunelling of alpha particle bcz i have a problem in this topic
رحم الله والديك
Could you make videos on astrophysics , electricity &waves (physics igcse)
Thank you SOO MUCH
Cognito is best to explain i always see your video and understand i have a book that i made... it is written cognito understanding book 😂 which i always study from that book i made my self its easy for me in exams ❤😊 that i always use
No use meat riding bro hes not seeing this
easy to understand videos
He is amazing brahh!!
So, if I had 1kg of a radioactive substance, and its activity was, say, 30Bq. If I had 20kg of it, would the activity be the same, or would it multiply by 20?
I love you cognito man
But,instead of dividng the no. of nuclei by the no. of half-lives, we can just take the no. of half-lives as an index of 2, rght?
Hi everyone,
Could you please help me with this following question
Radioactive materials are considered to be relatively safe when their
activity has fallen below 0.1% of their initial value.
(a) How much half-lives does this take? (Answer = 10 half-lives)
(b) Plutonium-239 is a by product of nuclear reactors. Its half-life is
24 000 years. How long does the plutonium-239 have to be stored as
nuclear waste before it is considered safe to handle? (Answer - 240 000
years)
no wait im sory
im not sorry
rats? i was in a room with rats. rats.
͓̽T͓͓͓̽̽̽H͓͓̽̽E͓̽ ͓̽F͓͓̽̽O͓͓̽̽G͓̽ ͓̽I͓͓̽̽S͓̽ ͓̽C͓͓̽̽O͓͓̽̽M͓͓̽̽I͓͓̽̽N͓͓̽̽G͓̽
͓̽T͓͓͓̽̽̽H͓͓̽̽E͓̽ ͓̽F͓͓̽̽O͓͓̽̽G͓̽ ͓̽I͓͓̽̽S͓̽ ͓̽C͓͓̽̽O͓͓̽̽M͓͓̽̽I͓͓̽̽N͓͓̽̽G͓̽
͓̽T͓͓͓̽̽̽H͓͓̽̽E͓̽ ͓̽F͓͓̽̽O͓͓̽̽G͓̽ ͓̽I͓͓̽̽S͓̽ ͓̽C͓͓̽̽O͓͓̽̽M͓͓̽̽I͓͓̽̽N͓͓̽̽G͓̽
͓̽T͓͓͓̽̽̽H͓͓̽̽E͓̽ ͓̽F͓͓̽̽O͓͓̽̽G͓̽ ͓̽I͓͓̽̽S͓̽ ͓̽C͓͓̽̽O͓͓̽̽M͓͓̽̽I͓͓̽̽N͓͓̽̽G͓̽
͓̽T͓͓͓̽̽̽H͓͓̽̽E͓̽ ͓̽F͓͓̽̽O͓͓̽̽G͓̽ ͓̽I͓͓̽̽S͓̽ ͓̽C͓͓̽̽O͓͓̽̽M͓͓̽̽I͓͓̽̽N͓͓̽̽G͓̽
͓̽T͓͓͓̽̽̽H͓͓̽̽E͓̽ ͓̽F͓͓̽̽O͓͓̽̽G͓̽ ͓̽I͓͓̽̽S͓̽ ͓̽C͓͓̽̽O͓͓̽̽M͓͓̽̽I͓͓̽̽N͓͓̽̽G͓̽
͓̽T͓͓͓̽̽̽H͓͓̽̽E͓̽ ͓̽F͓͓̽̽O͓͓̽̽G͓̽ ͓̽I͓͓̽̽S͓̽ ͓̽C͓͓̽̽O͓͓̽̽M͓͓̽̽I͓͓̽̽N͓͓̽̽G͓̽
͓̽T͓͓͓̽̽̽H͓͓̽̽E͓̽ ͓̽F͓͓̽̽O͓͓̽̽G͓̽ ͓̽I͓͓̽̽S͓̽ ͓̽C͓͓̽̽O͓͓̽̽M͓͓̽̽I͓͓̽̽N͓͓̽̽G͓̽
In the question at the end, I did (5/40) x 3,000,000
Which equalled the same answer, 375,000.
I don't know how my brain saw this as logic or how I did that but is this method also correct??
Thanks
I have a question.sodium-24 decays at a rate of 2.6 per day,calculate it's half-life?
Sorry the question was sodium-24 decays at a rate of 2.6 count per day , calculate it's half life
16 seconds in and I'm bored. Off to a new video!
hope you got a u
you got goldfish attention
6:11 or you could do 3,000,000/(2)^3
these vids are a smart way to get views ngl (but they'r gud soooo)
Where is Black mesa???
clearly explained. Thank you
thank youuu
If anyone is wondering, the formula for calculating half life is
c * 0.5^t
c is the original amount (here 3000000)
t is the amount of half lives (here 3)
An you get the amount after 3 half lives
You're welcome 🙂
Ok, can someone explain this to me? I just cant figure it out. If there were an istoped with a half life of one year and you possessed 2 samples of it. Sample A) 10lb and sample B) 1lb. After one year would you have 5lb of A and 1/2 of B? If so then it would seem that the decay rate isn't the same. Bc you managed to decay 5lb in one year in sample A but in sample B only 1/2 pould decayed after 1 year. What am I missing?
Hello, idk if you already got an answer to this since it's been 2 months.
The thing is that since the atmos have a certain chance of decaying after a certain time, see it like this.
Every second, each unstable atom throws a dice, if it lands on 1, it decays into a stable atom, if it lands on any other number, then it will continue being unstable.
So, every second, each atom has a chance of decaying of 1 in 6.
That means that after the first second we'd expect a sixth of our original sample to become some other element, so we're left with 5/6 of what we began with, if we had 36 atoms at first, we would now have 30, we lost 6 atoms. Then, after the next second, it's not going to be reduced by 6 again, now we're working with 30 unstable atoms, and since a sixth of them decay, we would now be left with 25, which is 5 less.
Of course, in real life the chances are not a sixth every second. But with this example it's noticeable that decay is proportional to the sample, SO it's never a fixed amount.
In your example it's first a 10lb sample and a 1lb sample, they decay into 5lb and 1/2 lb. In total it went from 11lb to 5.5 lb, proportion of decay stays the same.
Half life: 3 confirmed?!?!??!
If my half live is a decimal number, is it okay to just divide the # of substance to the # of half lives directly?
Like if my half lives is 18.67
Are you trying to carbon date?
more like inCOGNITO
Smn tell me who the editor is cuz he deserves a round of a plause 💀
Im gonna cry i think
Theres no saving you being a dumbass finally caught up with you
I want to know the time taken 🤪🤪
i acc love you
why did you have to Multply the 5 days by 24 hours
it confusing me
because we need to know how many hours we have in 5 days to divide by 40
@@guard9142 oh okay
@@guard9142 veryyy late reply thou
my gcse is in two days
@Cognito
Hi!!! I was wondering if it would be possible to figure out how long it would take for something to reach ONE radioactive nucleus
I have a sample of 80 trillion and a half life of 30 years!! (Chernobyl and cesium137) so would the formula of
80 trillion/2^(x/264115) = 1 and solve for x work, giving me the time it would take in hours?
... do you still need help with that question..?
how do you observe a half of 1000000000 billion years when they have only noticed it takes place for 70 years
ooOMfG GUYYSSS ItSss HALFF LUfe maDe Bi Volvo
I have no idea what I'm doing
Anyone else giving igcse in 2020?
yes
hate to break it to you, but that kinda looks shaky now
Meh
I’m in visual arts, why am I watching this??
Our teacher gave us a somewhat the same question but the problem is that i got 9,475.2488733336 when I divided the days from the half-life. Soooo, does that mean that I need to halve the 3.2x10^15 that many times. *sigh 😔*
Hmmm I think I'll have to recheck it.
O my gosh, Since the video's example says 5days, I accidentally tried to solve mine using 5days as a given when the real given states only an hour.
1/10 video not enough crowbars
i was looking for a physics analysis from the *game* "Half-Life", but science is cool
where’s gordon freeman
gordon freeman is a highly trained professional!
He doesn't need to hear all this!
Rise and shine, Mr Freeman.
Not that I wish to imply you have been sleeping on the job
@@seowyy No one is more deserving of a rest... and all the effort in the world would have gone to waste until... well, let's just say your hour has... come again.
@@electroblastz The right man in the wrong place can make all the difference … in the world. So, wake up, Mister Freeman. Wake up and … smell the ashes.
@@MD-dw5eeI didn't see you get on
Where's the 3 half life coming from in the question??
5 days x 24 hours =120 hours
40 hrs=1 half-life
number of half-lifes= 120/40= 3 half-lifes
i see where the half life decay dlc got its name from
someone get this King his crown
teaching myself chem bio and physics so thank you for explaining everything - I’ve recommended u to basically everyone Ik
Ah thank you! Glad you've found the channel helpful
Gordon doesn’t need to hear all of this, he’s a highly trained professional - half life game scientist
Who's Gordon?
@@meenakshibhat6713 he’s from a video game called half life
Oh