DIY Science: Is the 5-second rule true?

Eureka! Lab takes on the question: Is the 5 second rule true? To find out, we need to do some science!
Four blog posts accompany this video (click for more):
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[HSkk-yium]

If anyone needs the independent variable or dependent variable for this experiment, they are:
Independent variable - amount of time that the food stayed on the floor
Dependent variable - amount of bacteria that grows on the food

[acecelia]

I'm already dead inside from this homework so why'd you haveta go and waste that icecream cone man

[k.korshumov]

Hello! How did you exactly determine the number of colonies in each Petri dish using ImageJ? Is there a specific tutorial on how to do that with the software? If yes, I would be glad if you could share it. Thank you in advance.

[aantony]

The results don't seem consistent with the conclusion that dropping food is bad. @ 3:50 The graph shows that "never dropped" had the most growth. And both 50s samples had fewer colonies than respective 5s. Is the data saying that dropping doesn't matter? And if you drop, then let it sit longer before you pick it up?

[mathieugrenier]

You say : as soon as your food touches the floor you suffer the consequences but how can such a claim be made when even the condition in which you did not drop it was full of bacteria ?

[ciao]

This helped me a lot, it was very interesting to see a rule that has been around for so long be debunked, and your sense of humor is very entertaining.

[sunnshineschupp]

how many days did it take to complete the experiment?

[msk]

Have you heard a little thing called "Twitch prime"

[stevejeffryes]

Instead of this test which provides data, try this thought experiment which may provide a valid conclusion: Does eating food off the floor (or ground) harm animals? Very few bacteria survive the acid bath in the stomach.

[celestemartinez]

What is the difference between the control and the never dropped plates?

[ACAx]

You should do how to get rid of pimples painlessly

[andernaugle]

How would I quantify the results with a statistical chi-square test? (I’m thinking about testing the 5 second rule as well for a research paper for my biology class).

[sunnshineschupp]

Wait so how many petri dishes did she use.

[LymuvThissler]

So, the longer food stays in contact with the floor the less bacteria it will grow. Good to know. You just supported the 50 second rule! Actually it doesn't matter. What this really shows is that most likely if it was safe to eat before you dropped it, it is still safe to eat after you drop it. As long as you don't intentionally try to promote bacterial growth by providing a nice incubator for days afterwards.

[cameron-white]

The instructions on your blog are poor. I followed them exactly, but my agar agar gelatine mixture didn’t turn out yellow, it instead turned out clear but cloudy, then dried up over a few days. We failed our primary school science experiment because of this.

[JackAttackCat]

are candles needed? and Do u have to have a dirty and clean group?

[donnellebradley]

Did the bacteria increase dramatically or stay fundamentally the same

[aghosh]

Its my birthday .... and after watching this vdio i want to thnk u . Such inquisitive mind . Keep doing sciency things. Made my birthday great bcause i watched a good vdio

[ggsap]

Our teacher played this video in the class and we could not stop laughing on some parts of how stupid it was..

[g.prabhatkumar]

what if i dropped ice cream and then just collected uppermost part of it leaving half of the ice cream touching the ground ?