Why is g = +9.8 in the g-force and acceleration formula when gravity acts downwards? (1 Viewer)

[Prawnchip]

*chosen direction is upwards

 

[AnimeX]

Re: Why is g = +9.8 in the g-force and acceleration formula when gravity acts downwar

*chosen direction is upwards

So the formula is thrust-mg / m (apparent weight/true weight), taking g as -ve would work here.

I think your version of the formula takes into account the negative and makes it positive for you.

 

[Chris100]

Re: Why is g = +9.8 in the g-force and acceleration formula when gravity acts downwar

No, I think Prawnchip is talking about the g-force=1+a/g and why the g is positive and not negative since gravity acts downwards where the positive is in the upwards direction.

The g is positive because the g-force equation aims to determine the RATIO between a and g, and since it's just a ratio, g is taken as a positive

 

[braintic]

Re: Why is g = +9.8 in the g-force and acceleration formula when gravity acts downwar

g is not positive.

The g force is the DIFFERENCE between the acceleration due to gravity and your acceleration (as a fraction of g).

ie. g-force = 1 - (-a/g)

 

[Prawnchip]

Re: Why is g = +9.8 in the g-force and acceleration formula when gravity acts downwar

No, I think Prawnchip is talking about the g-force=1+a/g and why the g is positive and not negative since gravity acts downwards where the positive is in the upwards direction.

The g is positive because the g-force equation aims to determine the RATIO between a and g, and since it's just a ratio, g is taken as a positive

Thanks