Bunsen Bites — small bites, big discoveries

We're going to find the one rule that makes that possible, and it fits in three words: force times distance. Then we'll find out what that rule secretly charges you, because nothing comes free, not even in physics.

No machine gives you something for nothing. Every one of them obeys moment = force × distance, and the units, newton metres, tell you why. A small force at a big distance equals a big force at a small distance. That's the whole trick behind the wheelbarrow, the pulley, the bike gear and your own arm.

Sources:

• https://www.geeksforgeeks.org/physics/types-of-lever/
• https://www.vedantu.com/jee-main/physics-levers
• https://study.com/learn/lesson/muscle-levers-body-systems-examples.html
• https://foreverwingman.com/asvab/mechanical-comprehension/levers/

Source: Episode 17 - Physics Level 8, Simple Machines (17/17)
Style: Exam prep
Length: 900 words, 5 min target
Generated: 2026-10-25

We're going to follow Watt as he tries to put a price on a horse's effort, and that will show us exactly what work and power are. Then we'll open your electricity bill and see that you're paying for the thing Watt was trying to measure.

The listener can explain why the highest-wattage appliance in the house might not be the one that costs the most. They can also say the three formulas in order: work = force × distance in joules, power = work ÷ time in watts, and cost = kW × hours × price per kWh. Watt's failed pricing scheme is the system their family pays under today.

Sources:

• https://en.wikipedia.org/wiki/Horsepower
• https://www.scienceabc.com/eyeopeners/engine-power-measured-steam-engine-horsepowers-name-watt
• https://www.hagerty.co.uk/articles/automotive-history/the-work-and-life-of-the-man-who-invented-horsepower/

Source: Episode 16 - Physics Level 8, Work and Power (16/17)
Style: Exam prep
Length: 973 words, 6 min target
Generated: 2026-10-25

It doesn't know anything. It just blocks every road heat can travel, and there turn out to be two kinds of road: one you can block by taking stuff away, and one that doesn't need any stuff at all.

The flask is a heat-blocking checklist. The vacuum stops the two particle routes, and the shiny walls fight the route that needs no particles. That is why it works both ways: it doesn't care which direction the heat is going.

Sources:

• https://en.wikipedia.org/wiki/Vacuum_flask
• https://www.scienceabc.com/innovation/thermos-flask-keep-hot-things-hot-cold-things-cold
• https://www.docbrown.info/ephysics/wavesaaer-3.htm
• https://en.wikipedia.org/wiki/Leslie_cube

Source: Episode 15 - Physics Level 8, Heat on the Move (15/17)
Style: Exam prep
Length: 978 words, 6 min target
Generated: 2026-10-25

Here's the deal: we're going to follow every single joule out of a dying phone and find out where it actually goes. Then we'll hit a weirder question: if all that energy is sitting in your room right now, why isn't your room roasting?

Your phone didn't destroy its energy. It smeared it across the whole room, adding loads of joules but almost no degrees, until everything reached the same temperature. 'Dead' doesn't mean empty. It means spread out. Now the listener can say that energy (J) is conserved and transferred between stores, that wasted energy is dissipated to the surroundings, and that temperature (°C) is not thermal energy (J). Thermal energy depends on mass, material and temperature: about 4200 J to warm 1 kg of water by 1 °C.

Sources:

• https://cdn.bad.org.uk/uploads/2022/01/29200046/James-Prescott-Joule.pdf
• https://collection.sciencemuseumgroup.org.uk/objects/co2526/mechanical-equivalent-of-heat-apparatus
• https://www.aps.org/apsnews/2009/12/joule-abstract-converting-mechanical-heat
• https://mcq.sg/blog/heat-vs-temperature
• https://physicstribune.com/thermodynamics/heat/
• https://homework.study.com/explanation/what-has-more-heat-a-cup-of-boiling-water-or-a-bathtub-full-of-20-o-c-water-why.html
• https://www.gauthmath.com/solution/1812633355147333/2-A-cup-of-water-and-a-bathtub-full-of-water-are-at-the-same-temperature-but-hav

Source: Episode 14 - Physics Level 8, Energy and Temperature (14/17)
Style: Exam prep
Length: 1166 words, 6 min target
Generated: 2026-10-25

We'll follow one Mars bar from the wrapper into you, then follow the same idea into a power station. By the end you'll know why some energy runs out forever and some never does, and it comes down to whether you're spending today's sunlight or sunlight from millions of years ago.

You and a power station are both sunlight-spenders. The Mars bar is this year's sunlight, caught by plants. Coal is ancient sunlight, and we're spending it far faster than it was saved. The listener can now say what energy is measured in (kJ), work out a portion from a label, and explain renewable versus non-renewable in one sentence: does the store refill?

Sources:

• https://avzri.com/how-much-energy-is-in-a-mars-bar-per-100g

Source: Episode 13 - Physics Level 8, Food, Fuel and Power Stations (13/17)
Style: Exam prep
Length: 1170 words, 7 min target
Generated: 2026-10-25

This episode chases one idea: a magnet with an off switch. First we'll see what you can do by switching it on and off, then what happens when you flip it back and forth fast enough to make sound and spin a motor.

The motor is the bell's trick grown up. The bell interrupts itself to keep ringing, and the motor reverses itself to keep spinning. A magnet that never gets where it's going is what makes things move.

Source: Episode 12 - Physics Level 8, Electromagnets at Work (12/17)
Style: Exam prep
Length: 814 words, 5 min target
Generated: 2026-10-25

We're going to work out why the North Pole is secretly a south pole, using nothing but the rules of magnets. Then we'll find out that the Earth isn't really a magnet like the one on your fridge at all. It's something you can build on a kitchen table.

The 'wrong' pole name is the rules working correctly. The planet's magnet isn't a lump of magnetised rock but moving metal, the same idea as the coil you can build with a nail, a battery and some wire. The listener leaves able to say which way field lines run, why the North Pole is magnetically south, and the three ways to make an electromagnet stronger.

Sources:

• https://www.esa-spaceweather.net/why-earths-magnetic-north-pole-keeps-drifting/
• https://www.ncei.noaa.gov/products/wandering-geomagnetic-poles
• https://www.kinocranes.com/how-are-electromagnets-used-in-scrap-yards/

Source: Episode 11 - Physics Level 8, Magnets and Electromagnets (11/17)
Style: Exam prep
Length: 999 words, 6 min target
Generated: 2026-10-25

We're going to run your house wired the wrong way, watch it fall apart, then rewire it the right way. Along the way you'll get the two rules electricians live by.

Houses are wired in parallel so every device gets full voltage and works on its own. The price is that the currents add up in the wire feeding them. The listener leaves able to state both rules with symbols and units. In series, current is the same everywhere and voltages add up. In parallel, voltage is the same on every branch and currents add up. They can also say which one their house uses and why.

Sources:

• https://eshop.se.com/in/blog/post/series-vs-parallel-circuits.html

Source: Episode 10 - Physics Level 8, Series and Parallel (10/17)
Style: Exam prep
Length: 961 words, 5 min target
Generated: 2026-10-25

The bird's secret is that a volt isn't something a wire has. It's a difference between two points. We'll chase that idea until it gives us one equation, and by the end you'll be able to work out exactly why the bird lives.

The bird isn't tough. The maths protects it. Small V over big R means almost no I. The listener leaves able to say what potential difference is and how to measure it, state R = V/I in ohms, and rearrange it with the triangle to explain a real-world puzzle.

Sources:

• https://www.electronics-notes.com/articles/history/pioneers/georg-simon-ohm-biography.php

Source: Episode 9 - Physics Level 8, Voltage and Resistance (9/17)
Style: Exam prep
Length: 1149 words, 8 min target
Generated: 2026-10-25

We're hunting for the one difference between those two. First we'll make charge pile up and stay put, then we'll let it go and count it as it moves, and by the end you'll know exactly what an amp is counting.

The spark and the glow differ in one thing only: whether the charge keeps moving. A zap is a pile that empties all at once. A light is charge passing steadily, and amps are just the count of how much gets by each second, which is why the counter has to stand in its way.

Sources:

• https://en.wikipedia.org/wiki/Coulomb
• https://www.schoolphysics.co.uk/age11-14/Electricity%20and%20magnetism/Current%20electricity/text/Charge_and_current/index.html
• https://www.physicsclassroom.com/class/estatics/Lesson-2/Charging-by-Friction
• https://www.ck12.org/flexi/physical-science/electric-charge-and-electric-force/what-is-the-process-for-charging-a-balloon-with-static-electricity/

Source: Episode 8 - Physics Level 8, Charge and Current (8/17)
Style: Exam prep
Length: 1107 words, 6 min target
Generated: 2026-10-25