Question

for the acceleration due to gravity that is 9.8m/s2 [down], is it same as -9.8m/s2 [up] or the negative sign indicates that down is negative and up is positive?

Answer 1

Answer:

The Negative sign indicates that the acceleration due to gravity is towards downward

It is based on the assumption taken by you....

You can also assume down is positive and up be negative

but both the signs are necessary.........

Answer 2

it's not necessary that, in down direction u have to take positive value.......u can choose acceleration in the upward direction as positive....and coreponding to this downward as negative.......

solving the question,u will get the same answer in both the cases.....

Note:signs ,have a very important,role...in solving numericals...its important to understand,it's meaning......