What is the earth's average density?

Question

An object's average density is defined as a ratio of its mass to its volume M/V. The earth's mass is 5.94*1024 kg, and its volume is 1.08*1012 km^3 .What is the earth's average density?

Answer 1

The density equation is given in the problem statement.

 

density = mass/volume

 

The mass and volume are also given, so we simply divide the given mass by the given volume. Note that the volume is given in km³, so we should convert that to m³ if you need your density in kg/m³

 

To convert km to m, we multiply by 1000. We have km³, though, so we do this conversion three times. 1.08x10¹² km³ * (1000 m / 1 km)³ = 1.08x10²¹ m³

 

We use the density formula now and plug in our values

 

density = 5.94x10²⁴/1.08x10²¹ = 5500 kg/m³

density = 5500 kg/m³

 

I hope this helps! If you have any questions, please ask.