What is the relationship between g and a in physics?

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In physics, 'g' represents the acceleration due to gravity, typically valued at -9.8 or -9.81 meters per second squared, depending on the coordinate system used. 'a' is a general variable for acceleration and can take on various values in different scenarios. While 'g' is a specific case related to gravitational acceleration, 'a' encompasses all forms of acceleration. The negative sign in 'g' indicates the direction of acceleration in relation to the chosen coordinate system. Understanding this distinction clarifies the relationship between 'g' and 'a' in physics.
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what's the difference between a and g?? i think i know that g will almost always be associated with -9.8 meters per second squared, and that a can be any other number in many different cases ... so that's it? g is always -9.8 ??
 
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a is the general variable for acceleration.

g is just one special case since we use it all the time for gravity.

also g = 9.8 or 9.81... the - comes from the problem and how you setup your coordinate system.
 
ok thanks i got it
 
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