The Sun’s angular diameter is measured to be 1920′′. The distance D of the Sun from the Earth is 1.496 * 10^{11} m. What is the diameter of the Sun ?

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Formula To Calculate Arc Length With Solved Examples
Example Questions Using the Formula for Arc Length. Question 1: Calculate the length of an arc if the radius of an arc is 8 cm and the central angle is 40°.
For more information, see Formula To Calculate Arc Length With Solved Examples
Given that
Sun's diameter d = ?
Distance between the Sun and Earth D = 1.496 * 10^{11} m
Angular diameter of the sun \theta = 1920''
\theta = 1920 * 4.85 * 10^{-6} rad
\theta = 9.31 * 10^{-3} rad
Step 1: Develop a figure using the details provided.
Step 2: Finding the diameter of the sun
From the figure:
AB is a diameter of the Earth
Assumption: AB is considering as a arc.
Arc length d = D \theta
d = 1.496 * 10^{11} * 9.31 * 10^{-3}
d = 1.39* 10^{9} m
Hence, diameter of the sun d = 1.39* 10^{9} m