Posted by ashley on Saturday, June 11, 2011 at 1:37am.
Assuming that 68.1% of the Earth's surface is covered with water at average depth of 1.21 mi. ,estimate the mass of the water on Earth. One mile is 1.609 km and the radius
of the earth is 6.37 x 10^6 m. Answer in units of kg

physics  drwls, Saturday, June 11, 2011 at 3:40am
The volume in cubic meters is the product of the ocean area (in m^2) and the average depth (in meters).
For the ocean area, take 68.1% of 4*pi*R^2.
For the mass of the water, multiply the volume by 1000 kg/m^3. Actually you should use a higher density of 1027 kg/m^3, corresponding to ocean salt water, since that is what most of it is.
Calculating these numbers yourself will improve your learning experience

physics  ashley, Sunday, June 12, 2011 at 3:32pm
I multiplied 68.1 X 5.099043638x10^14=3.472448717x10^16 to get the ocean area.
Then to get the average depth i took 1.21mix1609m=1946.89.
Then i multiplied the ocean area and volume i got to equal 6.760475683x10^19.
To get the mass, I took that answer and multiplied it to 1000 kg/m^3. I got 6.760475683x10^22. If i put that in significant figures it woud just be 6.76 x 10^22 kg right? was my method correct?
Answer This Question
Related Questions
 Algebra 1  Earth has a radius of about 6.4 x 10 to the 6th power m. Approximate...
 physics  Assuming the Earth's magnetic field averages about 0.50×10−4 T ...
 Maths  Assuming the earth to be a sphere of radius 6370 km.If seventy five ...
 earth science  The global ocean covers about 70% of the Earth’s surface. If all...
 Earth Science  1. The water cycle is the _____. A. distribution of drinking ...
 Physics  A 1.0kg mass weighs 9.8 Newton on earth's surface, and the radius of ...
 physicsmechanics  A 1.0 kg mass weighs 9.8 N on Earth's surface, and the ...
 PHYSICS  Search: a 1.0 kg mass weighs 9.8 n on earths surface and the radius of...
 physics  A satellite of mass 225 kg is launched from a site on Earth's equator ...
 Physics  What is the Earth's gravitational force on you when you are standing ...
More Related Questions