What are some simple experiments in finding sun's diameter with its respective procedure?

Question

What are some simple experiments in finding sun's diameter with its respective procedure?

Answer 1

Let's say you have a tiny hole in your roof. Sunlight coming through the hole will create a circle on the floor. If you measure the roof height and the circle diameter you can approximately calculate the sun's diameter (if you are allowed to use the distance between earth and sun; otherwise the experiment will be little bit more complicated with further loss of already poor precision)