Proving the density equation! ρ = m / V | Live Experiments (Ep 21) | Head Squeeze

Jon Chase explains what density is and proves the formula 'density=mass/volume' works by manipulating the values in this fun demo.

IMPORTANT: Under-fives you will need a sober adult with a sense of scientific wonder....

The items you need to get started are: a few cans of lemonade or another soft drink (diet AND full fat), digital scales, a jug, a pint glass, a small container to capture displaced water, a small sealable plastic container, 16 two pence pieces, white vinegar, bicarbonate of soda and some tissue paper.

Experiment #1
1. Fill your pint glass or large jar up with water
2. Put the pint glass inside your container to capture the displaced water
3. Submerge the can in the pint glass
4. Now weigh this excess water on your scales
5. You can now deduct the weight of the can to get the figure for the displaced water

Experiment #2
1. Put some vinegar on one side of your small sealable container. Now put a small amount of bicarbonate soda on the other side (separate them with tissue paper as you don't want them to react just yet)
2. Keep the vinegar at the bottom side of the container so it doesn't leak through the tissue paper
3. Now seal the container.
4. Put 16 two pence pieces in a thin plastic bag and put your container in with them.
5. Now tie the bag in a knot
6. Drop the bag into a large tank or bath and it will sink
7. Now turn your container upside down and the reaction will start
8. The co2 released will cause the 2p's to rise to the top

Live Experiments: Our resident science demo thrill-seekers will give the YouTube audience their big science treat each week with an experiment where you can find out how to make food dance, power a light bulb with household objects and create mega smoke rings!

[ShatteredEquilibrium]

Such a great video, the world would be a better (and smarter) place with teachers like that at school.

[JoshinglyJosh]

Jon is a great guy, I met him once :)

[Slarti]

You are right - proof and theory have very specific meanings in science which many lay people do not understand.
As an aside many lay people also don't know that science does not use the word'fact' - there are reasons why science uses words in a specific manner.

[Username]

This video has taken shaky cam to a whole new level!

[MIKOLBZ]

I know him, He's a top guy & a super productive human being & we could do with a lot more people like him.

[Ghost]

that was a really good explenation for the volume being displaced by the solid object.

[AtticusHimself]

Before anyone complains about the absence of James May, yes his presence immediately increases the video quality by 128%, but with or without him, it's a video where you learn science! If you can't sit down and appreciate that, you don't deserve Youtube.

[MrXxTimmyXx]

Does that mean that the volume of a boat (anything from a barge to a aircraft carrier) has a lower density than water with that same volume?

[eshalarshad]

I understood evrything as soon as he started explaining, which is at about 1:37. Thank you <from Pakistan>

[Amydali]

Not sure if this has been asked but is 16 2 pence coins equal to 16 US 1 cent pennies? Not currency wise- density/ weight wise?

[richardmilecz-mityko]

But for most people they are the same. They both are: the guy who knows how stuff works.( I know the diference but I study physics in university so it's somewhat my job to know that)

[TheJeff]

the same man taught me the word 'peng'.

[ThyBountyHunter]

Considering the lifespan of an elephant, I am pretty sure there are grams, and maybe close to great-grams.

[Kenchan]

he does show it in the pictures even though he doesn't say it...

[george_plays]

Of course it isn't, but they could just have easily called the video "Demonstrating the density equation!"
Laypeople have a lot of trouble understanding scientific terms ("just a theory" is a perfect example of that), and I think it would help a lot if popular science communication used them correctly and consistently.

[JoeHartiganFleming]

Remember the units! 364 what? Elephants?

[trippyhippy]

You should have warned us to take any fish out the tank before the experiment the vinegar and soda bag burst and 3 fish died RIP Billy Bob, Jesus and Bengt :(

[TanerNilluhktaf]

Why front camera shakes so much? Makes me dizzy! Please change camera man.

[ruthvick.b]

You should minus the empty glass wt with the Glass with water weight

[williamjenkins]

Where I come from a CO2 bomb is a much different thing. A CO2 whippet filled with black powder.