Concept explainers
(a)
The mass of the dust.
(a)
Answer to Problem 70P
Explanation of Solution
Given Data:
Formula Used:
The Potential energy of the comet at the surface of earth is given as:
Mass of the dust
Calculation:
Gravitational Potential energy of comet:
The half of the gravitational potential energy is used to hold the dust particles:
Mass of the dust is calculated as below:
Conclusion:
Mass of the dust is
(b)
The mass density of the dust.
(b)
Answer to Problem 70P
Explanation of Solution
Introduction:
Density is defined as mass per unit volume:
The dust lies from earth’s surface to 20 Km in the atmosphere. Therefore, the distance is from R to R+20 Km.
The Volume between thesedistances is given as below:
Density of dust:
Conclusion:
Density of the dust is
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Chapter 7 Solutions
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