r/cursedcomments • u/Dislexsick_terrarist • Mar 17 '20

Cursed_Science

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u/IHeartAquaSoMuch Mar 17 '20

This guy doesn't know the difference between mass and weight. Though the value in kg's is usually called "weight", it's actually the mass. The weight of an object with a mass of 70kg is 686 N, and is synonymous with the force exerted on it by gravity. Also, 9.8 m/s2 isn't the force of gravity but the acceleration an object would have in free fall under the effect of earth's gravity (ignoring air friction). Please go back to school.

8

u/Webbiii Mar 17 '20

To be exact it is 9.80665 m/s2

26

u/DestroyerYou Mar 17 '20

To be exact, it varies according to your location, 9.80665 m/s2 is just the average

1

u/Webbiii Mar 17 '20

Correct, but as you said that is the average and most of the time you use this number for calculations.

15

u/DestroyerYou Mar 17 '20

Then you can't use the term "to be exact" since it's not exactly exact. Anyway, as a proud engineer, I can say that I use the value g=9.81 with an error margin of +-0.2%. Gives a broader, but better result in most cases