When an object is moving with uniform velocity, what is its acceleration?

"Acceleration" means change of speed or direction (or both).

"Uniform velocity" means constant speed in a straight line ... no changes.

So "uniform velocity" means acceleration is zero.

the earths atmosphere is made up of nitrogen and oxygen. solids can turn into gasses through a process called sublimation. sublimation is the transition of a substance directly from the solid to the gas phase, without passing through the intermediate liquid phase.

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