Why Though? with Dr. Matt Agnew

The ground beneath your feet feels completely still... but the continents are actually moving all the time.In this episode of Why Though?, Dr Matt Agnew explains why continents drift across the Earth, how tectonic plates slowly carry them around the planet, and how that movement creates mountains, deep ocean trenches and earthquakes.What you'll discover:Continents move just a few centimetres each year... about as fast as your fingernails growLong ago, every continent was joined together in one giant supercontinent called PangaeaEarth's crust is made of enormous tectonic plates rather than one solid shellWhen plates collide they can push up mountain ranges like the HimalayasWhen one plate slides underneath another, it creates deep ocean trenches through a process called subductionEarthquakes happen when pressure builds between stuck plates before suddenly being releasedWhy Though? The show for little scientists who love asking big questions. Subscribe so you never miss an episode.Also available on Spotify and Apple Podcasts... search Why Though?Follow Dr Matt Agnew: Instagram: instagram.com/drmattagnew TikTok: tiktok.com/@drmattagnew YouTube: youtube.com/@whythoughpod Website: drmattagnew.comFind Why Though? podcast across the internet and share with your friends! Instagram: instagram.com/whythoughpod TikTok: tiktok.com/@whythoughpod Facebook: facebook.com/whythoughpod#whythough #scienceforkids #kidspodcast #dryice #sublimation #DrMattAgnew #STEMforkids #kidsscience #educationalpodcast #Australiakids #curiouskids #chemistryforkids #familypodcast #statesofmatter #sciencefacts Hosted on Acast. See acast.com/privacy for more information.

It looks like magic. It makes spooky fog that pours down instead of floating up. And it never leaves a puddle. So what is dry ice actually doing?Dr Matt Agnew unpacks the weird science of dry ice, what sublimation is, why the fog pours downward like a waterfall, and why dry ice behaves so completely differently from the ice in your freezer.What you'll learn:Normal ice is frozen water... dry ice is frozen carbon dioxide, the gas we breathe outDry ice skips the liquid step entirely... straight from solid to gas with no puddleScientists call that process sublimation, one of the most interesting phase changes in scienceThe fog is mostly not carbon dioxide at all... it's water vapour from the surrounding air getting chilled so fast it becomes visibleCold air and carbon dioxide are both heavier than regular warm air, so the fog pours downward like a fog waterfallDry ice is essentially a natural fog machine used in theatres, film sets and Halloween displays worldwideKey Science Ideas:Sublimation: When a solid skips the liquid stage and goes straight to gasCarbon dioxide: The gas we breathe out, and what dry ice is made ofWater vapour: Invisible water in the air that becomes visible when it gets suddenly coldPhase change: When matter moves between solid, liquid and gas statesDensity: Why cold air and carbon dioxide both sink rather than riseSafety note: Dry ice is extremely cold and must only be handled by adults wearing insulated gloves. It should only be used in well ventilated spaces. This is a watch and learn episode.Why Though? The show for little scientists who love asking big questions. Follow or subscribe so you never miss an episode.Follow Dr Matt Agnew: Instagram: instagram.com/drmattagnew TikTok: tiktok.com/@drmattagnew YouTube: youtube.com/@whythoughpod Website: drmattagnew.comFind Why Though? podcast across the internet and share with your friends!Instagram: instagram.com/whythoughpodTikTok: tiktok.com/@whythoughpodFacebook: facebook.com/whythoughpod Hosted on Acast. See acast.com/privacy for more information.

A cheetah? A race car? A rocket? All great guesses. All completely wrong. The fastest thing on Earth is something you can't hold in your hand... and understanding it means understanding lightyears, the speed of light, and why space distances break normal numbers.Dr Matt Agnew runs the ultimate speed race from Usain Bolt all the way to the speed of light, and explains what a lightyear actually is along the way. Spoiler... most adults get it wrong.What you'll learn:Usain Bolt tops out at around 44 kilometres per hour... the slowest in this race by a long wayA cheetah sprints at 100 to 120 kilometres per hour... basically a furry rocketAn F1 car reaches around 350 kilometres per hour... blink and it's goneNASA's Parker Solar Probe is the fastest human-made object at 690,000 kilometres per hourLight travels so fast it feels instant... and in one second it can circle the entire Earth about seven timesA lightyear isn't time, it's distance... how far light travels in one whole year, about 9.5 trillion kilometresThe closest star to Earth after our Sun is Proxima Centauri, just 4.2 lightyears awayKey Science Ideas:Speed of light: About 300,000 kilometres per second... the ultimate speed limit of the universeLightyear: A unit of distance, not time... how far light travels in one whole yearProxima Centauri: The closest star to Earth after our Sun, 4.2 lightyears awayParker Solar Probe: NASA's spacecraft and the fastest human-made object ever builtAstronomical scale: Why scientists need special units like lightyears to measure enormous distances in spaceFun Experiment: The Lightyear Myth Buster Ask three people in your house or school what a lightyear is. Most will say it's a unit of time. They're wrong... it's distance. Explain that a lightyear is how far light travels in one year, about 9.5 trillion kilometres. You've just done your first myth-busting science experiment, and you didn't need a single piece of equipment.Why Though? The show for little scientists who love asking big questions. Follow or subscribe so you never miss an episode.Why Though? The show for little scientists who love asking big questions. Follow or subscribe so you never miss an episode.Follow Dr Matt Agnew: Instagram: instagram.com/drmattagnew TikTok: tiktok.com/@drmattagnew YouTube: youtube.com/@whythoughpod Website: drmattagnew.comFind Why Though? podcast across the internet and share with your friends!Instagram: instagram.com/whythoughpodTikTok: tiktok.com/@whythoughpodFacebook: facebook.com/whythoughpod Hosted on Acast. See acast.com/privacy for more information.

Have you ever walked outside on a bright sunny day and suddenly sneezed... with no dust, no pepper, no cat fluff anywhere? Just sunshine and a sneeze? There's a real science reason behind it.Dr Matt Agnew investigates the sun sneeze mystery. What even is a sneeze? Why does bright light trigger one for some people? And why does it run in families?What you'll learn:Sneezing is your body's nose cleaning button... a blast of air that clears anything annoying from your mucous membraneWhen bright sunlight hits your eyes, your brain urgently signals blink and squintFor about 1 in 4 people, the blink button and the sneeze button sit really close together in the brain... so pressing one accidentally bumps the otherScientists call this ACHOO Syndrome... short for Autosomal Dominant Compelling Helio-Ophthalmic OutburstSun sneezing is linked to your genes, which means it can run in familiesSun sneezes won't hurt you... but stop before the sneeze hits if you're on a bike or crossing the roadKey Science Ideas:Mucous membrane: The sticky lining inside your nose that catches dust, germs and anything annoyingOptic nerve: The nerve that carries signals from your eyes to your brainACHOO Syndrome: The scientific name for sun sneezing... and yes, the acronym was absolutely intentionalGenes: The instructions inside your body that decide things like eye colour, height, and apparently whether sunshine makes you sneezeReflex: An automatic body response your brain triggers without you choosing itFun Experiment: The Family Sun Sneeze Survey Ask everyone in your family whether they sneeze when they look at bright light. Try a torch in a dark room if the sun isn't cooperating. Keep track of who does and who doesn't. If sun sneezing runs in your family, you'll start to see a pattern... and you'll have just conducted your first genetics experiment at the kitchen table.Why Though? The show for little scientists who love asking big questions. Follow or subscribe so you never miss an episode.Follow Dr Matt Agnew: Instagram: instagram.com/drmattagnew TikTok: tiktok.com/@drmattagnew YouTube: youtube.com/@whythoughpod Website: drmattagnew.comFind Why Though? podcast across the internet and share with your friends!Instagram: instagram.com/whythoughpodTikTok: tiktok.com/@whythoughpodFacebook: facebook.com/whythoughpod Hosted on Acast. See acast.com/privacy for more information.

Here's something nobody tells you. Most of a fart has absolutely no smell. So what's actually making everyone pinch their nose?Dr Matt Agnew investigates the science of farts. How do smells actually work? What is a fart made of? And why do some foods make the whole situation so much worse?What you'll learn:Smells are tiny invisible particles floating in the air that your olfactory receptors grab and send to your brainA fart is gas made by bacteria in your intestines while they break down foodMost fart gas has absolutely no smell... nitrogen, hydrogen, carbon dioxide, oxygen and even methane are all odourlessThe real culprit is hydrogen sulfide... just 1% of a fart but enough to clear a roomFoods like beans, eggs, broccoli, brussels sprouts, garlic, onion and cheese all produce more hydrogen sulfideMost people fart between 10 and 20 times a day... farts are natural, healthy, and a sign your body is doing its jobAstronauts on the International Space Station have to think carefully about farts because the gas can be trapped and even flammableKey Science Ideas:Olfactory receptors: The tiny parts inside your nose that detect smell and send signals to your brainBacteria: Tiny living things in your intestines that help break down food... and make gas while doing itHydrogen sulfide: The gas responsible for that rotten egg smell... and basically every bad fart everIntestines: The long tube where food gets broken down after leaving your stomachMicrobiome: The community of bacteria living inside your body doing useful work every dayFun Experiment: The Food Fart Tracker Pick two days this week. On day one eat a meal with plenty of broccoli, beans or eggs. On day two eat a meal without any of those. Pay attention to what happens a few hours after each meal. That difference is hydrogen sulfide in action... your gut bacteria working harder on certain foods and producing more of that one very specific gas. Science is everywhere, even when you'd rather it wasn't.Why Though? The show for little scientists who love asking big questions. Follow or subscribe so you never miss an episode.Follow Dr Matt Agnew:Instagram: instagram.com/drmattagnewTikTok: tiktok.com/@drmattagnewYouTube: youtube.com/@whythoughpodWebsite: drmattagnew.comFind Why Though? podcast across the internet and share with your friends!Instagram: instagram.com/whythoughpodTikTok: tiktok.com/@whythoughpodFacebook: facebook.com/whythoughpod Hosted on Acast. See acast.com/privacy for more information.