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Why can floating in the air still take a lot of power?

An airship can get support from buoyancy and still need power to travel. Balancing its weight does not remove the drag created when its large body moves through the surrounding air. A floating balloon and a powered airship therefore pose two related questions: what keeps them up, and what lets them go where someone wants?

3–5 min

Questions you could explore

  • Why does motion relative to the air matter more for drag than speed over the ground?

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Physics

Why metal can feel colder than wood

A metal handle and a wooden tabletop can share a room temperature yet feel quite different. The clue lies in the exchange of heat between your hand and the surface, which is not the same thing as measuring temperature.

5–7 min

Why metal can feel colder than wood

Physics5–7 minA metal handle and a wooden tabletop can share a room temperature yet feel quite different. The clue lies in the exchange of heat between your hand and the surface, which is not the same thing as measuring temperature.

Physics

How can headphones fight noise with more sound?

A steady engine hum can fade when noise cancellation switches on, while a nearby voice remains noticeable. The electronics and the physical ear covering do different jobs, and neither makes every sound disappear.

4–5 min

How can headphones fight noise with more sound?

Physics4–5 minA steady engine hum can fade when noise cancellation switches on, while a nearby voice remains noticeable. The electronics and the physical ear covering do different jobs, and neither makes every sound disappear.

Physics

How can a ship made of steel float?

A solid piece of steel sinks, yet a steel ship can carry people and cargo. Its hollow shape changes how much water the whole vessel can push aside, making the material alone an incomplete explanation of floating.

3–5 min

How can a ship made of steel float?

Physics3–5 minA solid piece of steel sinks, yet a steel ship can carry people and cargo. Its hollow shape changes how much water the whole vessel can push aside, making the material alone an incomplete explanation of floating.

Why can floating in the air still take a lot of power? | Speech Topic | speaking.app