Negative Acceleration of Gravity

Most recent answer: 11/12/2013

Q:
HOW we take acceleration due to gravity negative when it is against the surface of earth,is it have any mathematical derivation?
- hafsa ilyas (age 16)
karachi,pakistan
A:

You get to pick whatever direction you want to call "positive". If you pick "up" then since gravity goes down you call it negative. But it's your choice.

Mike W.


(published on 11/12/2013)