Why is the sky blue?

Why does water boil?

What doesn't superfluid boil?

How can a superconductor have 0 resistance? Is it really 0 or just very small?

How does my oven work?

How does my microwave work?

Why don't solar electric panels trump gasoline and coal?

Why does the earth have a magnetic field?
(Trick question. No one knows. We think there are currents of molten iron inside the earth that carry charges in knotted loops... Why there is any rotation that is out of sync with the surface rotation is a mystery. Viscous drag should have dampened irregularities in the flow so that the entire globe would be spinning at a constant rotation rate by any known model.)

Is it true that everything is radioactive? (yes)
If it's true that everything's radioactive... then what's the big deal with radiation?

Does the fact that the position wave function of every particle that is "me" or "you" or anything occupies the entire universe with a non-zero value mean that we're all connected in a mystical kind of way?

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Just throwing you guys a few softballs.. seems like you've lost the spark of curiosity.