Earth's Gravitational Force On Me

[Zack Davis]

I am working on a problem to sate my own curiosity. :) My mass is approximately 85.1 Kg. The Earth's mass is approximately (5.972x10^24 kg) and the distance between our center of masses is roughly the same as the Earth's radius of (6371 km) so I was wondering; what would the Earth's gravitational force be between the two of us. My answer is 8.3514...x10^8 N
(Using the formula:
F=G ( (m1xm2)/r^2) )
Am I correct? Thank you!

 

[Drakkith]

Oh my, no. One kilogram is equal to about 9.8 Newtons here on Earth, so you should be getting about 834 Newtons, or 8.34x10². It looks like you've made some sort of order of magnitude error, but I can't be sure.

 

[NascentOxygen]

Hi Zack Davis. http://img96.imageshack.us/img96/5725/red5e5etimes5e5e45e5e25.gif

Your answer is a little greater than expected. I was thinking more like 85.1x9.81 N

Did you convert distance to metres for that formula?

 

[Drakkith]

Did you convert distance to metres for that formula?

I bet that's it. 6,000 Km squared is 3.6x10⁷, but 6,000,000 meters squared is 3.6x10¹³, a difference of 6 orders of magnitude, which is how far off his final value is.

 

[Zack Davis]

I found the problem, I was acting as though I am a celestial body! Haha. Thank you all for the help!