at what angle does the sun gives more direct rays and less direct rays? (small or large angle)?

Answer 1

The old professor says: In optics, the incident ray angle (in this case, the one from the sun) is always measured against a "normal" which is an imaginary line drawn at ninety degrees to the surface (in this case, the surface of the Earth) upon which the incident ray strikes. The most direct rays of the sun would thus be the ones that are at ninety degrees to the Earth's surface (the large angle). As the angle goes from ninety degrees down to zero, the rays of the sun are spread out over a greater area, so the concentration of insolation (incoming solar radiation) gets less per square unit of area. The intensity of insolation is measured in "langleys". The sun can reach the ninety degree elevation anywhere between 23.5 degrees north and south of the equator. It can get to zero degrees anywhere on earth...at sunrise or sunset.

Answer 2

During the winter, when the sun is shining at a small angle, more air is heated, but the ground stays cold. The air is catching all the sunlight, and the ground is getting less sun per square inch than it is in the summer. So during the summer, when the sun is at a large angle, we get the most direct rays. During the winter, our atmosphere gets the most direct rays.

Answer 3

THE SUN DOES NOT CHANGE IT IS THE EARTH THAT IS TILTED. That angle does not change.