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Series 1: 2. You Could Dig Through the Earth?
The deepest hole humankind ever dug only got one thousandth of the way through the earth. But what would happen if you kept digging?
Source: CBBC
Most recent episodes of Hey You What If?
Hey You What If?
Series 1: 24. You Took All The Water Out Of The Sea?
Empty the oceans and you’d see hidden wonders, but you’d also cause the end of the world.
05-11-2024
CBBC
Hey You What If?
Series 1: 23. You Could Teleport?
Is it really possible to teleport? Spoiler alert: it could end in disaster!
29-10-2024
CBBC
Hey You What If?
Series 2: 21. You Built The Tallest Building On Earth
So you want to build the tallest building on Earth? Ambitious but good on yer! This episode will tell you how, starting with how not to. \n\nMost tall buildings are tall and th ...
25-10-2024
CBBC
Hey You What If?
Series 1: 22. You Could Build A Gingerbread House?
It’s the ultimate baking challenge: making a gingerbread house you could actually live in.
22-10-2024
CBBC
Hey You What If?
Series 2: 20. You Threw A Ball Round The World
To throw a ball around the world, you need to start out in space, throw it ten times the speed of a bullet and make sure your ball does not explode when it hits the atmosphere.
18-10-2024
CBBC
Hey You What If?
Series 1: 21. You Woke Up As A Lizard Superhero?
Why waking up with lizard powers would make you useless on earth but a superhero in space!
15-10-2024
CBBC
Hey You What If?
Series 2: 19. You Only Ate Burgers
If everyone in the world ate nothing but cheeseburgers, we would run out of land, and even if we went meat-free, we would have to invent some crazy burgers to get the nutrients ...
11-10-2024
CBBC
Hey You What If?
Series 1: 20. You Try To Catch A Falling Star?
What happens if you try to catch a falling star? Spoiler alert - probably best not to try!
08-10-2024
CBBC
Hey You What If?
Series 2: 13. You Were The Last Person On Earth
What would the planet be like if all other humans disappeared, leaving you as the last person on earth?
06-10-2024
CBBC
Hey You What If?
Series 2: 18. There Were No Colours
Imagine removing all the colours one by one? It would change more than just how things look, and after taking out just three colours, we would not be able to see anything at all!
04-10-2024
CBBC
Most popular episodes of Hey You What If?
Hey You What If?
Series 1: 25. You Could Switch Off The Sun?
See what would happen if you really could switch off the sun.
13-06-2022
CBBC
Hey You What If?
Series 1: 17. You Could Live In Slow Motion?
Find out why living in slow motion would let you see things no-one else can!
01-11-2023
CBBC
Hey You What If?
Series 2: 6. You Lived On Venus
Venus has acid rain, crushing pressure, and is hotter than an oven, so it might not sound like the ideal place to live. However, up in the clouds it's almost just like home.
09-09-2024
CBBC
Hey You What If?
Series 2: 16. Money Grew On Trees
If you had a tree that could grow money, would that make you rich? Even if you wait 20 years for your tree to grow, you will probably end up no richer than you started.
04-09-2024
CBBC
Hey You What If?
Series 1: 10. The Earth Was Flat?
Find out why a flat earth would feel very unflat indeed!
22-12-2023
CBBC
Hey You What If?
Series 2: 22. You Had Kangaroo Legs
Running a marathon is hard. At least it is for a human. But what if we could swap our legs with an animal – would that make it any easier? \n\nFirst, we try ...
03-10-2023
CBBC
Hey You What If?
Series 2: 10. Your Mind Could Move Things
We imagine a world where it's possible to move things with your mind like films, but find that the laws of physics mean that this superpower wouldn't quite work like you'd expect.
13-09-2024
CBBC
Hey You What If?
Series 1: 7. Clouds Were Made Out Of Cotton Wool?
Clouds might look like cotton wool, but if they really were, things would get very messy.
19-12-2023
CBBC
Hey You What If?
Series 1: 21. You Woke Up As A Lizard Superhero?
Why waking up with lizard powers would make you useless on earth but a superhero in space!
15-10-2024
CBBC
Hey You What If?
Series 2: 8. You Were Invisible
We try out three potential ways to become invisible and discover some surprising side effects.
11-09-2024
CBBC