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Not with light — atoms are far smaller than the wavelength of visible light, so no optical microscope can ever resolve them. The images you have seen come from instruments that feel surfaces or use
An extremely light, electrically neutral particle that interacts with matter so weakly that trillions pass through your body every second without effect — which is exactly what makes them both nearly
By a travelling electrical pulse generated by ions moving across the cell membrane, then converted to a chemical signal to cross the gap to the next cell — an electrical-chemical relay rather than a
A measure of the average kinetic energy of the particles in a substance — how vigorously they move, vibrate and rotate. It is not a measure of how much heat something contains, and separating those
Because you must force atomic nuclei — all positively charged and therefore violently repelling each other — close enough to fuse, which requires conditions comparable to the inside of a star, and
By measuring a change in the length of a four-kilometre laser beam path smaller than a fraction of the width of a proton — an almost absurd measurement that took decades to make possible. What is
Through a ladder of methods, each calibrated against the one below it — because no single technique works across the enormous range of distances involved, and the whole structure is only as sound as
A vast electrical discharge between regions of separated charge — and the honest position is that how the charge separates in the first place is still not fully settled, which surprises people about
By running a chemical reaction that is physically split in two, forcing the electrons to travel through your circuit to get from one half to the other. That separation is the whole idea. The
Through the photovoltaic effect — light knocking electrons loose in a semiconductor, with the material's structure arranged so those electrons flow in one direction rather than simply recombining.
Because of whether a material has electrons free to move, which in turn depends on how its atoms share them — and the answer is genuinely quantum-mechanical rather than a matter of how tightly
Because the waves are bunched up ahead of the source and stretched out behind it — the Doppler effect, which is one of the few pieces of physics you can hear directly. The mechanism. A siren emits
From several independent lines of evidence that agree, the first and most direct being that almost every distant galaxy is moving away from us, faster the further away it is. The original
Almost entirely from earthquakes. Seismic waves travel through the planet and arrive at stations around the world subtly changed by everything they passed through, which makes the Earth its own
No. It is one of the most thoroughly disproved claims in popular science, and essentially every line of evidence contradicts it. What the evidence shows: Imaging. Functional MRI and PET scans show
Not in your sink, no. The Coriolis effect is real and genuinely does act in opposite directions in the two hemispheres — but it is far too weak to determine which way a basin drains. What the
Three properties, all following from the fact that laser light is produced by a coordinated process rather than a chaotic one: it is a single colour, the waves are in step, and the beam barely
It does not make cold — it moves heat, pumping it from inside the cabinet to the room, which is why the back of a fridge is warm and why leaving the door open heats a kitchen rather than cooling it.
By shaking water molecules with an oscillating electric field — not, as the common explanation has it, by hitting some special resonant frequency of water. The actual mechanism. A water molecule is
Magnetism comes from electrons, and specifically from a quantum property called spin — the everyday picture of a magnet as containing tiny arrows is closer to correct than most simplifications,
Through two cooperating systems — one fast and general, one slow and specific — and the key insight is that they solve different problems and that the second one remembers. Innate immunity: fast and
Atoms of the same element with different numbers of neutrons — so they share chemical behaviour but differ in mass and, crucially, in nuclear stability. The distinction that defines it. An element is
Clouds form when air cools to the point where it can no longer hold its water vapour, and they stay up because the droplets are so small that air resistance almost entirely offsets their weight. Why
By solving physics equations on a grid, starting from the best available picture of the atmosphere right now — and the limits of forecasting come from the fact that small errors in that starting