Question

I wanted to know when discussing free fall what is easier to make acceleration negative or positive

Answer 1

I personally go with negative...it makes the direction of the acceration clear.

Answer 2

What if we are discussing for example an object thrown upward would acceleration still be negative?

Answer 3

yes...because the acceleration due to gravity is still pointing down

Answer 4

I think most people use the same convention...the acceleration due to gravity is negative no matter what the direction motion is.

Answer 5

oh because I have seen in problems in which they make acceleration due to gravity negative and some they make positive it confuses the heck out of me

Answer 6

Yea, it can get confusing when people consider it positive. You just have to consider the situation of each problem....force diagrams help keep your signs right

Answer 7

When you move on to gravitational forces, they are always attactive and the Fg in those problems is therefore always negative too. That's another reason to stick with it being negative.

Answer 8

IE: the force of gravity between to objects is:\[Fg=-G\frac{m1m2}{r^2}\]

Answer 9

yeah you are right! I am in Physics I we haven't even seen that yet.

Answer 10

Good luck :) Physics can be pretty fun once you get the hang of things

Answer 11

thank you hope your right.

Answer 12

always it is taken as -ve to solve problems not because of the gmm/r^2 part
negative sign there just tells us that the body is bound to earth(has to do with energy)

as for this sign always take g as negative