GCSE Physics - Efficiency #8
ฝัง
- เผยแพร่เมื่อ 7 ก.พ. 2025
- In this video we cover:
The idea that devices aren't 100% efficient
What efficiency is
The equation for efficiency
Examples of how to calculate efficiency
Why some devices like electric heaters are sometimes considered to be 100% efficient
General info:
Suitable for all GCSE and IGCSE courses
Exam board specific info:
AQA - Everything is relevant to your course!
IGCSE Edexcel - Everything is relevant to your course!
Edexcel - Everything is relevant to your course!
OCR 21st Century - Everything is relevant to your course!
OCR Gateway - Everything is relevant to your course!
If you’d like to practise the material covered in this video, check out our platform at www.cognitoedu.org - it'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
nothing is 100% efficient except Cognito
edit : future me here i am now in the second year of a levels and i just felt nostalgic so i checked this comment and why dose this have 600 likes and why did i make 100+ comments on this channel
and a heater...
@@MI-lo2hj no because a heater isn't a device because it's 100% efficient and cogi said devices arent 100% efficient
@@Wojbest_YT bruh look 10 seconds after that
@@Wojbest_YT heaters produce thermal waste energy whihc is acctually useful unquote
ur moms pretty efficient
Not going to lie but what my teacher took 2 hours worth of lessons to explain what you did in 5 minutes. You make teaching look easy. Thank you for this.
yh
i thought i was gonna die in the middle of the physics exam .. i watched 27 videos of the physics playlist nonstop ...
i swear to god my brain was digesting stuff i thought they were hard and i did well in the exam
Tysm Cognito I will edit this comment and tell you the results :D
97 outta 100 :>
I hope it went well! Did you get your results yet?
@@belladormer6918 I got 97 out of 100 c:
@@m7md_bss its good
@@laethferas4214 ty mate
all thanks to cognitooo
@@m7md_bss damn bro I have my physics exam tomorrow morning
Cognito is my only hope
I'll tell you the results when I get them
This channel is a hidden gem.
Thank you so much !!!
1000% true
Last minute mock gang where u at? 😭
Here omg I have mock in 3 hours and I just started studying
5 months later
HEREEE
Last minute finals gang here 😈 safe to say I'm fked in this physics exam
we here
Me😭 class of 2025
thank you omg you're so underrated
Thankyouuu Fatima! 😊
@@SajjadAli-er4fh her username prolly was fatima b4 and she changed it later
I recommend this channel as a cheat code to your exam .share it so the world can have more genius people.🗿🗿
Got a really important science test soon so thanks for this I needed to refresh my knowledge on it all , thankyou :)
Hope the test went well 🤙
Full a* brudda
@@Cognitoedu You are so amazing. What i do is i watch the video, re-watch it making notes and turn notes into colourful posters. It is incredibly helpful and makes me suceed in exams much better so huge thank you as could not do it without your help!!
@@Cognitoedu Before using your videos was getting grade 3 and 4 is science and was thinking about doing foundation. but after using your videos now getting 6, 7 and 8 and going higher. Thank you!!!
@@oscarpeters103 woah gd for u
I’m in year 9 and yet these videos are so helpful! Thankyou so much cx
Really happy to hear they’re helping!
same
me 2
Finnaly finished this topic energy all you videos help so much thank you.
not going and lie you actually made this topic sound soo simple
bro i watched a couple of your vids just before my exam and if it weren't for you two of my exam pages would be empty thank you sooo much
Really glad we could help AllRoundGamer!! 👍
You saved me today mate 😧
These videos are all way great and helpful 😊❤👌
Great Video! Really easy to follow and understand! Keep up the brilliant work!
thank you so much... this video is a lifesaver!
these videos are so helpful, thank you!!
I appreciate you letting us comment
fr
Thanks for this helpful video! It helped a lot with the understanding of efficiency.
ur videos came in clutch for my exams so thanks man
Great to hear Afnan, hope your exams go well! 🤞
reteaching myself all my physics before y11 bc i dont get any of jt, you guys rlly helpp
This is great! Thank you!
You saved my life
cognito is the best and the thumbnails are so good
Ah thank you so much Beulah 😊
Thank you cognito. ❤
Watching this a few hours before my monthly:)
Legend 🙌🙏👑
your videos are so helpful, thank you so much!!!
Great video, easy to understand, thanks!
Thank you! 😊
Good science teaching bro
04:43
Electric Heaters also produce waste energy... in the form of SOUND
very helpful, especially when i need to revise for exsams
Glad to hear that Gacha 👍
Thanks a lot make more of these videos
Why is youtube so much better than the actual lessons?
Thanks a lot for this I wasnt sure about this subject till I watched this 😛✋🏽
Glad it was helpful Amelia 👍
@@Cognitoedu Alya probably changed her name
Thnx this rlly helped I subbed
Thanks for the sub! 😊
Anyone else got this video prepared because there meant to be revising incase ur mum walks in haha
Man just saved me from depression 😭
Thank you for this
Is it same like for example charger brick
Input is 230v output is 5v.
How about appliances that shows only input?
thank you for the help it was so helpful appreciate you doing this for everyone here
Glad we could help you articwolf
That actually cleared some doubts, thanks!
Hey Ani thanks for the comment! Really happy to hear it cleared things up for you - good luck with the rest of your work! 🙌
@@Cognitoedu Nam
Wow,best explanation ever. 👌👌
Swear, got an exam tmrw and this video explaining the whole thing, i dont need to study more?
well explained .. thank you.. keep it up
Hey thanks for the support really appreciate the kind words! And also TY for leaving us a comment it really helps the videos get seen etc 💛
Well explained!
ik this is quite late but don you x100 after you do your calculations?
Thanks for this
thankyou i really needed serious help BTW thanks
i love these videos, they a short and concise
Nice video
thank you I have an assessment tmr and i forgot how to calculate effiencency with decimals !
Thank you so much sir
You legend
Like it, nice!
Energy isn't always transferred into the energy that's intended because nothing is 100% efficient,some become wasted energy which means useless energy
Formula= useful energy output/total energy
TYYY SO MUCH MY PHYSICS TEACHER DOES'NT TEACH PROPERLY 😭😭
Thanks for the good explaining. So helpful.
Glad you liked it Imran 😊
An intimate discussion with Binance's CEO about future developments
Ur Videos are the best, checking my answers, you helped me get it right
In business and in life, may you wear a smile.
thx so much! this is a really good video!
Thxs I needed that
You’re welcome!
Got a physics across the board next period
thanks i got exam tomorrow
I’m doing this in physics but with time variables which make it a bit harder. I also have to use power output instead of this one.
Can light energy be counted as wasted energy for heaters?
Yes light + noise too
Is the total power input in horsepower or normal power
thanks this helped a lot
Great video! Just wanted to ask if for the energy transferred in a lightbulb, you could start with electrical energy (even though it is not an energy store, would this still get you full marks in an exam?). And then this would be transferred electrically in wires, to thermal energy to the surroundings, and lighting the bulb?
Electrical-->light+heat (I think)
this is the most use ful vid eveaaaa
👏👏👍 👍
yeah I enjoyed it 🧣🦧🤧
Well explained.... thnx!
Hey thank you for leaving us a comment, and really happy to hear it’s helpful to you!
Thanks
no u
It's the effectively of convertion of energy most waste products are in the form of heat and nothing has 100 percent efficiency (no waste products)
thank you so much
Many thanks
Love it
Can someone explain to me what is the difference of GCSE And IGCSE
IGCSE just means 'international GCSE', so it's a slightly different course done across the world (but most topics are pretty similar)
@@Cognitoedu thank you so much
Thank you!
When you explain it, it is hundred percent easier than my teacher teaching it 😊😊😊😊
I always use the percentage for efficiency
Binance's CEO opens up about future developments in an exclusive interview
the information is correct of course (probably), but you don't need to be getting people through school on a computer??????
very good vedio really helped me out thanks alot👌👌👏👏👏
Please explain in urdu
You are 💯🧑💻
Thank you so much this is really useful!!!
Glad you liked it 😊
I enjoyed it r u happy
But i am intelegant too 😐😐
perfect
Nice thanks. xoxo
wait a minute in my opinion just divide like a 225 divided by 45 answers are same
The last weekend before mock….
unlike everyone else no matter how much i watch this i dont get it!!
Honestly it takes a while sometimes fir me too
But whenever I start answering questions myself it sinks in more
Even if your comment was (approximantly) 2 years ago its definitely normal for this to happen sometimes im really good at understanding a certain topic but the next time i coudnt even grasp the concepts of others you just need to take it lightly and practice a bit more maybe extra practice questions or search other resources but in the end its natural so dont feel to bad (*´ ˘ `*)
Last exam today. Only need 60ish marks for 9-9
it's pretty clear now thanks to you
For the question with two lamps, can't you just divide the useful output of energy of the second lamp by that of the first lamp? Surely if the input energy of the two lamps is the same, there is no need to use the equation? Thanks for the video though, it really helped!
Seriously, more expected actions for a refund?