As the earth rotates, the sun appears to move 360$^{o}$ around the earth in 24 hours. By measuring the amount of time it takes the sun to move the length of its diameter, one can use the following formula
$\frac{\Delta t}{24 hrs}=\frac{\theta }{360^o}$
$\theta =\frac{360 \Delta t}{24 hrs}$
to solve for the sun's angular size.
Process
Set up a piece of paper so that the sun, when focused through a lens, falls on the page. Use a pencil to mark the right side of the sun's image. Start a stop watch AT THE SAME TIME because the sun's image is always moving across the page. Stop the timer as soon as the left side of the sun's image touches the mark you made before. The time you measured is the time it takes for the sun to move the length of its angular diameter.
Repeat the above process multiple times. Team Crush repeated the process thrice and got the same time measurement for each one. Each time, it took the sun 2 minutes and 14 seconds to move the length of its diameter.
Results
With our measurements and the above formula, we found that the angular size of the sun is 0.57$^{o}$ or $9.74\times 10^{-3}$ rad.
Hi Moiya, while you do a good job covering the basics here, a few diagrams would help your explanation a lot, as well a more details regarding the physical setup of the lab.
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