Explore Westonci.ca, the top Q&A platform where your questions are answered by professionals and enthusiasts alike. Discover the answers you need from a community of experts ready to help you with their knowledge and experience in various fields. Experience the convenience of finding accurate answers to your questions from knowledgeable experts on our platform.

The Earth is not a uniform sphere, but has regions of varying density. Consider a simple model of the Earth divided into three regions-inner core, outer core, and mantle. Each region is taken to have a unique constant density (the average density of that region in the real Earth):
Region Radius (km) Density(kg/m3)
Inner Core 0-1220 13,000
Outer Core 1220-3480 11,100
Mantle 3480-6371 44,00
A) Use this model to predict the average density of the entire Earth.
B)The measured radius of the Earth is 6371km and its mass is 5.974*1024kg Use this data to determine the actual average density of the Earth.


Sagot :

Answer:

Explanation:

Volume of inner core = 4/3 π R₁³

where R₁ is radius of inner core so R₁ = 1220 km

Volume of inner core = 4/3 π (1220 km )³

= 1764.4 x 10¹⁷ m³ - 4/3 π (1220 km )³

= 76.02 x 10⁸ x 10⁹ m³

= 76.02 x 10¹⁷ m³

Density = 13000 kg / m³

mass = volume x density

= 76.02 x 10¹⁷ x 13000

= 988.26 x 10²⁰ kg

Volume of outer  core = 4/3 π (3480 km )³ -  4/3 π (1220 km )³

= 1764.4 x 10⁸ km³ - 4/3 π (1220 km )³

= 1764.4 x 10⁸ x 10⁹m³ - 4/3 π (1220 km )³

= 1764.4 x 10¹⁷ m³ - 4/3 π (1220 km )³

= 1764.4 x 10¹⁷ m³ - 76.02 x 10¹⁷ m³

= 1688.38 x 10¹⁷ m³

density = 11100 kg /m³

mass of outer  core= 1688.38 m³ x10¹⁷ x  11100 kg /m³

= 18741 x 10²⁰ kg

Volume of outer mantle  =  4/3 π (6371  km )³ - 4/3 π (3480 km )³

= 10826 x 10¹⁷ m³- 1764.4 x 10¹⁷ m³

= 9062 x 10¹⁷ m³

density = 4400 kg /m³

mass of outer  core= 9062 x 10¹⁷ m³ x  4400 kg /m³

= 39872.8 x 10²⁰ kg

Total mass of the earth = 988.26 x 10²⁰ kg + 18741 x 10²⁰ kg +39872.8 x 10²⁰ kg

= 59602.06 x 10²⁰ kg .

Total volume = 4/3 π (6371  km )³

= 10826 x 10¹⁷ m³

Density = mass / volume

= 59602.06 x 10²⁰ kg /  10826 x 10¹⁷ m³

= 5505.45 kg / m³

B )

Mass = 5.974 x 10²⁴ kg

volume = Total volume = 4/3 π (6371  km )³

= 10826 x 10¹⁷ m³

density = 5.974 x 10²⁴ kg / 10826 x 10¹⁷ m³

= 5518.2 kg / m³