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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