Bunsen Bites — small bites, big discoveries

That invisible flash is a cousin of the light you read by, and of your microwave, your dentist's X-ray and sunburn. They're all one family. By the end you'll know the family in order, why they all travel at the same speed, and how a thing's place in the line tells you whether it heats your dinner or damages your cells.

The listener can recite the spectrum in order. They can state that all of it moves at the speed of light and crosses a vacuum, and they can predict from where something sits in the line whether it's a handy tool or a hazard. The one ordered line explains both halves of the topic, uses and dangers.

Sources:

• https://courses.ems.psu.edu/astro801/content/l3_p4.html

Source: Episode 7 - Physics Level 8, Invisible Light (7/17)
Style: Exam prep
Length: 1289 words, 7 min target
Generated: 2026-10-25

By the end you'll know why that shirt goes black. First we take white light apart to see what's inside it. Then we see that every coloured thing you've ever looked at is really throwing light away.

Back to the shirt, and now the listener can explain it themselves. A red object only reflects red. Green light contains no red. So nothing bounces back to your eye, and you see black. Colour was never in the shirt. It was in the light.

Sources:

• https://spark.iop.org/newtons-visible-spectrum
• https://www.vedantu.com/question-answer/explain-newtons-experiment-by-which-he-proved-class-12-physics-cbse-61559cfe8ec0356042a8b957
• https://en.wikipedia.org/wiki/Visible_spectrum
• https://www.britannica.com/science/primary-color
• https://www.wtamu.edu/~cbaird/sq/2015/01/22/why-are-red-yellow-and-blue-the-primary-colors-in-painting-but-computer-screens-use-red-green-and-blue/
• https://www.britannica.com/science/RGB-color-model

Source: Episode 6 - Physics Level 8, Light and Colour (6/17)
Style: Exam prep
Length: 849 words, 5 min target
Generated: 2026-10-25

So today's question is: how do you steer something moving at 300,000 kilometres every second? It turns out light only lets you do two things to it, bounce it or slow it down, and by the end you'll know the exact rule for each.

Two rules, one invisible line. Reflection: the angle of incidence equals the angle of reflection, measured in degrees from the normal. Refraction: when light crosses into a new material it changes speed, measured in km/s, and that change of speed bends it toward or away from the normal, unless it arrives straight along the normal. The listener can now explain the Moon mirror, a periscope, and the lens in their own eye.

Sources:

• https://www.schoolphysics.co.uk/age11-14/Light/text/Refraction_/index.html
• https://eclipse.gsfc.nasa.gov/SEhelp/ApolloLaser.html

Source: Episode 5 - Physics Level 8, Bouncing and Bending Light (5/17)
Style: Exam prep
Length: 1131 words, 7 min target
Generated: 2026-10-25

We're going to work out exactly what a sound has to be for your ears to catch it, and then why bats deliberately make the ones you can't. By the end you'll be able to calculate how small a bat's sound waves are, using one short formula.

The scream you can't hear is the bat's whole strategy. Push the frequency up past the edge of human hearing and the wavelength shrinks to the size of dinner. You can now prove it with v = fλ: 343 ÷ 100,000 is about 3.4 mm.

Sources:

• https://tractian.com/en/glossary/speed-of-sound
• https://en.wikipedia.org/wiki/Bat_detector
• https://en.wikipedia.org/wiki/Bat_species_identification
• https://cdn.bats.org.uk/uploads/pdf/Resources/Welsh-EdPack/05-Echolocation-Eng.pdf?v=1551107156
• https://arxiv.org/pdf/2407.15318
• https://www.vigienature-ecole.fr/en/node/102

Source: Episode 4 - Physics Level 8, Waves and Sound (4/17)
Style: Exam prep
Length: 1118 words, 7 min target
Generated: 2026-10-25

We're going to find out why a thing can be moving fast and still have its forces add up to exactly nothing. Then we'll take that idea somewhere much scarier: a person falling out of a plane.

The listener can now say: resultant force = the forces in one direction minus the forces in the opposite direction, measured in newtons. If it's zero, the object stays still or keeps a steady speed. If it isn't zero, the speed, the direction or the shape changes. They can also explain how a falling person can have zero resultant force, and why a parachute works by unbalancing the forces on purpose.

Sources:

• https://en.wikipedia.org/wiki/Terminal_velocity
• https://www.teachoo.com/10174/3050/Balanced-and-Unbalanced-Forces/category/Concepts/
• https://www.tes.com/en-us/teaching-resource/balanced-or-unbalanced-forces-tug-of-war-11080299
• https://www.tes.com/teaching-resource/new-aqa-gcse-2016-physics-resultant-forces-12265672
• https://www.aakash.ac.in/important-concepts/physics/resultant-force

Source: Episode 3 - Physics Level 8, Balanced or Not? (3/17)
Style: Exam prep
Length: 1073 words, 6 min target
Generated: 2026-10-25

We're going to solve this case. To do it, we need to learn to read one kind of motion graph, then catch the detective nearly arresting the wrong person because she read the second one the same way.

The case is solved by one habit: read the up-axis before the line. The listener leaves able to say speed = distance/time (m/s) and acceleration = change in speed/time (m/s²), and to explain why a flat line means opposite things on the two graphs.

Sources:

• https://www.olympics.com/en/news/usain-bolt-record-world-champion-athlete-fastest-man-olympics-sprinter-100m-200m
• https://www.britannica.com/story/how-fast-is-the-worlds-fastest-human

Source: Episode 2 - Physics Level 8, Motion Graphs (2/17)
Style: Exam prep
Length: 1153 words, 7 min target
Generated: 2026-10-25

We're going to work out what a scale actually feels when you stand on it, and what number it should really show. Then we'll take that scale somewhere else and watch the number change, even though you haven't changed at all.

The listener works out their own real weight. Take your kilograms and times by 10: forty kilos means 400 newtons. Then comes the twist. The scale was only ever guessing your kilograms by assuming it was on Earth. On the Moon it would be wrong, but your newtons would be the honest reading.

Sources:

• https://www.ssc.education.ed.ac.uk/BSL/physics/gravitationald.html

Source: Episode 1 - Physics Level 8, Forces and Fields (1/17)
Style: Exam prep
Length: 950 words, 6 min target
Generated: 2026-10-25

Today we're finding out what 'fittest' really means, and it isn't strongest or fastest. First we'll see what every living thing is actually fighting over. Then we'll see what happens when the rules of that fight change, and why scientists are freezing seeds just in case.

Survival of the fittest really means survival of whoever happens to fit. You can't train for it or choose it. That's why variety matters, and why a freezer full of seeds is an insurance policy against extinction. The listener can now explain natural selection in four steps: variation, competition, survival and reproduction, and inheritance.

Sources:

• https://en.wikipedia.org/wiki/Peppered_moth_evolution
• https://simple.wikipedia.org/wiki/Peppered_moth_evolution
• https://confidentials.com/manchester/strange-city-5-how-manchesters-moths-proved-darwin-right
• https://www.croptrust.org/news-events/news/article/svalbard-global-seed-vault-crosses-major-milestone-14-million-seed-samples-secured/
• https://en.wikipedia.org/wiki/Svalbard_Global_Seed_Vault
• https://www.seedvault.no/2026/06/18/svalbard-global-seed-vault-crosses-major-milestone-1-4-million-seed-samples-secured/
• https://www.frozenark.org/
• https://www.frozenark.org/what-we-do-overview

Source: Episode 10 - Biology Level 8, Survival of the Fittest (10/10)
Style: Exam prep
Length: 1148 words, 7 min target
Generated: 2026-10-25

We're going to work out who that animal is and why a forest needs it. To do that we'll zoom out step by step, from one animal to the whole forest, and then find out what happened when people took that animal away.

If you wanted to save the forest, your first instinct would be to protect the kelp, and that's the wrong answer. The right answer is to protect a furry animal that eats urchins. The listener can now state the five words (organism aside: habitat, population, community, ecosystem), sort any factor into biotic or abiotic, and explain interdependence using a chain they'll remember.

Sources:

• https://defenders.org/wildlife/sea-otter
• https://cimi.org/blog/the-keystone-species/
• https://www.britannica.com/video/keystone-species-parts-coast-kelp-forest-ecosystem/-174837
• https://www.marinemammalcenter.org/news/how-sea-otters-can-help-save-the-planet

Source: Episode 9 - Biology Level 8, Ecosystems (9/10)
Style: Exam prep
Length: 861 words, 5 min target
Generated: 2026-10-25

We're going to work out what that arrow really means. Then we'll follow it to the top of the food chain and find out why the animal everyone thinks is in charge is the one most likely to be in trouble.

The listener comes back to the opening question and now answers it correctly: the arrow points to the eater, because energy flows into it. They can explain why that same direction makes the top predator the most fragile animal, since it carries the most poison and is the first to starve. They also learn that the real power sits with the producers and the pollinators at the bottom.

Sources:

• https://nhpbs.org/wild/silentspring.asp
• https://blog.susnano.wisc.edu/2013/12/17/the-cautionary-tale-of-ddt-biomagnification-bioaccumulation-and-research-motivation/
• https://www.animalsaroundtheglobe.com/how-ddt-nearly-wiped-out-bald-eagles-in-the-20th-century-5-345130/

Source: Episode 8 - Biology Level 8, Food Webs (8/10)
Style: Exam prep
Length: 1000 words, 6 min target
Generated: 2026-10-25