Upthrust and Archimedes' Principle - A Level Physics

This video explains upthrust in fluids and Archimedes' principle for A Level Physics.
Why do objects float? Here I explain why the upthrust in fluids is equal to the weight of the displaced fluid (Archimedes' principle).
Thanks for watching,
Lewis
This video is recommended for anyone studying A Level Physics in the following exam boards:
AQA
CIE
Edexcel
Edexcel IAL
Eduqas
IB
OCR A
OCR B
WJEC
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[@amy_smith]

I think this man is single-handedly saving my A level

[@PhysicsOnline]

Thank you!

[@freezy2755]

What grade did u get?

[@Iugeer]

what grade did you get

[@Ashxxii]

@@Iugeerungraded💀

[@icaki4520]

U got great pens!

[@sheikhsaad2755]

😘😘😘 I wish my teacher could have atleast have 10% of your abilty of explaining things so nicely.

[@jasper642]

upthrust=buoyancy?

[@depression4091]

3:00 shouldnt the density be of the fluid instead of the object?

[@Wehn.]

It should

[@beastboysupper4353]

Musks,ye

[@nahilismail9619]

can you explain to me why weight is not used in this calculation?

[@yunanasey]

i know this is an arbitrary question, but what type of pens do you use? They're so nice!

[@PhysicsOnline]

WHO YOU What type of pen do I use?th-cam.com/video/5599WQd9uUI/w-d-xo.html

[@tobankaugusareeya5696]

Thank u sir.....That really helped me a lot. hats off to u sir

[@charliewootton9614]

Could you please explain how R=pg(h+x)A - pghA cancels to R=pgxA? I cant make sense of it 😭

[@PhysicsOnline]

You can expand the brackets to make R=pg(h+x)A - pghA equal to R=pghA+pgxA - pghA
The pghA terms cancel leaving pgxA

[@charliewootton9614]

+A Level Physics Online thank you!

[@elliottcooksey6886]

Does the weight of the fluid the body displaces = the weight of the object then?

[@sportmaster2586]

Do we need to know this for AQA A Level Physics?

[@gretawilliams8799]

+A Level Physics Online,
How are the Physics equations derived, like E=mc2?
Here, how was Archimedes sure that his working was real?

[@jeremiahmushtaq6520]

Is upthrust the same as drag because it counters weight in a fluid?

[@PhysicsOnline]

Jerry Mushtaq it's not the same, drag occurs when an object is moving. But upthrust will always act, even if it's stationary.

[@ggcvbvnbcby1424]

The area used is cross sectional area not the surface area just a reminder 😊

[@hharsh]

Why does R = F2 - F1? SHouldn't F2 = F1? :/

[@user-xw4mu6nz4t]

F2 is equal to F1.
But we're trying to find the resultant force, which is F2 - F1, and since they are equal the answer will be 0... But what if they weren't equal? Well watch the video and find out.

[@annoyingwalker]

Are we going to need to learn the derivation for this ??

[@NatSPlay]

Lol bit late fam

[@hamnachaudhary4657]

Are your videos also cover the course for CIE A levels...?

[@PhysicsOnline]

Hi - this is what I have for CIE: www.alevelphysicsonline.com/cie

[@specjade8613]

well, there you have it, 3 years of suffering solved in 3 minutes :'D
thank you.

[@carmendura141]

Is the block on minute 2:00 not moving?

[@user-xw4mu6nz4t]

Yes, the resultant force are 0 because the forces are equal yo each other.

[@billtensus]

can tell me how f=pgha
i am in class 8th i have learnt that f=pa

[@vikaspradhan2801]

F=PA,where P=pressure & A=area
but also P=pgh,where p=density of liquid(so called row) ,g=acceleration due to gravity,h= height
F=(P)A
F=(pgh)A
hence.F=pghA
note that P isn't equal to p

[@user-xw4mu6nz4t]

@@vikaspradhan2801 Also P isn't "P" (Pee), it's the Greek letter "Row" that looks like a tilted P.

[@jeremusthemedic2271]

*mind blown gif intensifies*

[@tobankaugusareeya5696]

Can U explain how F2 = pg(h+x)A???? Didn't get that part very well.

[@Ukid111]

+Dj AbdiYare Its essentially adding h. x is just h+h from the surface of the water to the bottom of the block (because you consider the height from both the top and the bottom of the diver to the surface.

[@user-xw4mu6nz4t]

So F1 is has a force of H but for F2 to counter it and balance out, it also needs to factor in the for x as the weight of x is also a force going downwards.

[@messaroundaccount1193]

Not going to lie you talk way too quickly in your explanations. You don't mind slowing down a bit please?

[@kuznetsov5172]

Mess Around Account rewatch it then

[@user-xw4mu6nz4t]

Good thing you can rewind and there's a playback speed option.

[@caprimbombartic5]

i hate examss

[@user-xw4mu6nz4t]

Exams hate you, thus balancing out the hatred like two equal forces lmao.

[@nahilismail9619]

can you explain to me why weight is not used in this calculation?

[@Iugeer]

well basically its because...

[@gretawilliams8799]

+A Level Physics Online,
How are the Physics equations derived, like E=mc2?
Here, how was Archimedes sure that his working was real?