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Omid
Sep10-04, 09:20 AM
Here is a discussion Question :

Overlooking the planet's own motion, why is it likely that everything moving for any appreciable distance on the surface of the Earth is accelerating?

Pleas help me with this question. I think it's talking about acceleration due to changing the velocity vector.
Thanks

Nenad
Sep10-04, 09:44 AM
its because the the earth is in rotation, and there is a centripital acceleration.

Tide
Sep10-04, 10:39 AM
Acceleration means rate of change of velocity. Velocity is a vector. If the velocity changes direction then acceleration occurs even if the magnitude of the vector remains fixed.

Locrian
Sep10-04, 10:44 AM
I'll add to what Tide said:

In space, just because things have a velocity does not mean they are accellerating. However, on earth, you will experience friction of one kind or another. That friction is an accelleration and therfore anything on earth should be experiencing it.

Banana
Sep10-04, 03:32 PM
I agree with Tide. You are supposed to ignore the earth's motion, but not the fact that the world is round. It's like when a car goes around a race track even at a constant speed, its velocity is considered to be changing because its direction is changing. And the definition of acceleration is 'a change in velocity'. So the earth is like a big round racetrack.