Concept explainers
Whether the orbital speed of earth or the speed of the earth about its axis or both is accountable for the study of radial velocities of the stars or not. Also, determine the value of the orbital speed and the speed of the earth about its own axis. Also, explain how astronomers compensated the effect of earth orbital speed and its speed about its axis.
Answer to Problem 80Q
Solution:
Explanation of Solution
Given data:
The stars radial velocity is to be measured to an accuracy of
Formula used:
The formula for radius of a sphere in term of diameter is:
Here,
The expression used for the circumference of a circle C of radius
The expression used for the speed
Explanation:
Refer to the appendix 1, the value of the orbital radius of the earth is,
The expression for the circumference at the orbit of the earth is,
Substitute
Use the expression of speed to write the expression of orbital speed of the earth.
Substitute
Refer to the appendix 2 to obtain the value of the diameter of the earth:
The formula for radius of earth is:
Substitute
Therefore, the radius of the earth is
The expression for the circumference of the earth at equator is:
Substitute
Use the expression of speed to write the expression of rotational speed of the earth.
Substitute
The orbital speed of the earth is
Conclusion:
The orbital speed of the earth is
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Chapter 17 Solutions
Universe
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