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Physics #286
Answered
DC vs AC Motor

Why do ceiling fans need AC instead of DC?

Chemistry #287
Answered
Why are elements arranged in groups and periods?

What’s the advantage of this structure?

Physics #288
Answered
Transformer Tactics

Why can’t we use transformers with DC?

Chemistry #289
Answered
Why does metallic character decrease across a period?

Why does sodium behave differently from chlorine?

Physics #290
Answered
Loudspeaker Magic

How does a loudspeaker convert electricity into sound?

Chemistry #291
Answered
Why are noble gases unreactive?

Why don’t they form compounds easily?

Physics #292
Answered
Magnetic Train Tech

How do maglev trains “float” above tracks?

Chemistry #293
Answered
Why does atomic size increase down a group?

What’s happening inside the atom?

Physics #294
Answered
Electric Bell Wonder

Why does an electric bell keep ringing as long as you press the switch?

Chemistry #295
Answered
Why is fluorine more reactive than chlorine?

Both are halogens, but fluorine is “fiercer.” Why?

Physics #296
Answered
Earth Without Magnetism

What would happen if Earth lost its magnetic field?

Chemistry #297
Answered
Why does electronegativity decrease down a group?

Why is oxygen more electronegative than sulfur?

Physics #298
Answered
MRI Machine Magic

How do MRI scanners “see” inside our bodies?

Chemistry #299
Answered
Why are alkali metals highly reactive?

Why do they explode in water?

Physics #300
Answered
Rainbow Reality

Why do rainbows always appear opposite the Sun?

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