### Easter Bouquet For AG

**Third Lily***Acceleration:*

The time rate of change of velocity. Since velocity is a directed or vector quantity involving both magnitude and direction, a velocity may change by a change of magnitude (speed) or by a change of direction or both. It follows that acceleration is also a directed, or vector, quantity. If the magnitude of the velocity of a body changes from v1 ft/s to v2 ft/s in t seconds, then the average acceleration a has a magnitude given by Eq. (1):(see above)

The time rate of change of velocity. Since velocity is a directed or vector quantity involving both magnitude and direction, a velocity may change by a change of magnitude (speed) or by a change of direction or both. It follows that acceleration is also a directed, or vector, quantity. If the magnitude of the velocity of a body changes from v1 ft/s to v2 ft/s in t seconds, then the average acceleration a has a magnitude given by Eq. (1):

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**Newton**by

Morri Creech

*A minor disappointment not to find*

*angels pushing the planets around their courses*

*as Leibnitz believed. A shame, but not a great one,*

*that the universe seemed less and less to hang*

*glimmering from God's chain like a golden fob,*

*although a pendent weight shaped Newton's thought.*

*Sitting alone there in that storied orchard,*

*he'd seen the apples drooping from their boughs;*

*until one formed, unplucked, a grand conclusion.*

*The apple fell because it had to fall,*

*as objects move toward objects, in accord.*

*It struck a dizzying tune into his head.*

*The clockwork of the heavens may make music,*

*but it was a grave music that he heard,*

*the whirl of mass, the hum of centrifuge,*

*and calculations on the page would prove*

*such motion both a falling and a flight.*

*Thus bodies spin each other round in space.*

*And gravity, too, becomes a kind of grace.*

-from "Some Notes on Grace and Gravity", from the collection Field Knowledge

## 1 Comments:

Um, I don't see it mentioned that acceleration is the derivative with respect to time of velocity, and the second derivative of position. Or that the acceleration of gravity on Earth is -9.8 m/s/s. Don't be lazy, A.V.!

And with apologies to Creech, Newtonian mechanics has several limitations when dealing with "heavenly bodies." The most obvious example of this is that Newton's third law lacks time as a variable: in the most common example, if the sun suddenly ceased to exist, the earth would not simultaneously go out of orbit, as it takes light, the speed limit of the universe, 8 seconds to get from the sun to the earth. The forces don't reciprocate simultaneously.

But a noble first effort, thank you!

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