# can wind be strong but not fast, or is fast and strong the same?

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can wind be strong but not fast, or is fast and strong the same?

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“Strong”= high force.

Force= Mass x Acceleration

The mass of atmosphere is essentially constant (with some variation as function of temperature).

So for wind to be “strong,” the strength must come from its acceleration/velocity.

I’ve read that even though other planets have high winds, like Mars, the air pressure/atmospheric density means to humans that even though the wind is like 100kph, the you’d still barely feel the wind. The wind can move fast, but it isn’t moving much. Like, a 60mph wind on Mars might feel closer to 6mph on Earth.

https://www.nasa.gov/feature/goddard/the-fact-and-fiction-of-martian-dust-storms

The force of wind acting on an object is defined by three variables:

The area of the object that the wind is striking.

The density of the air.

The velocity of the wind.

So technically you could have a weak force applied by a fast moving wind if the density of the air was very low (maybe at a high altitude or a planet other than earth).

Yes in principle, but not much in practice here on the surface of the Earth without changing altitude.

The force applied by a wind is (at least at low speeds) roughly proportional to its density times its speed squared. So to make the force vary, you need to make one of those terms vary. But here on the surface of the Earth, the density doesn’t vary that much. The lowest pressure (and thus density) ever recorded on the surface of the Earth was at the core of Typhoon Tip, the strongest tropical cyclone ever recorded. In Tip’s eye, the atmosphere was about 13% less dense than usual. The highest pressure (and thus density) ever recorded was about 7% *more* dense than usual, near the Dead Sea. So the density of air at sea level varies by at most about 20%.

That said: you can go higher! On top of a high mountain, half of the air is gone, so you will indeed feel significantly less force from a wind on a mountaintop. (That said, the wind speeds also tend to be a lot higher on mountaintops.)

It’s momentum. Which is product of mass and velocity. If you get hit by fast object, there will be collision and the velocity of the object reduces which is force.