Re: Acceleration constant
Your question is quite vague. The word of "acceleration constant" is meaningless. In general we usually refer to 'acceleration due to gravity' instead of 'acceleration constant'. It is because the magnitude of 'acceleration due to gravity' varies with the location of the objects. Different locations may have different values of acceleration due to gravity. For example, the 'g' value at equator is about 9.78 m/s*2 whereas its value at north or south pole is 9.81 m/s*2.
May be you are asking the gravitational constant G. It is a real constant irrespective to its location. The value of G is 6.67x10*-11 Nm*2/kg*2 . I hope the above explanation may help you a bit.