The front building is 49 meters high, and the back building is 55 meters away from the front building. Is there sun on the third floor of the back building on the morning of winter solstice?

At 9: 00 am, 10,1and 12 in winter solstice in Ningbo, the solar altitude angles are 22 38 ′, 30 20 ′, 3517 ′ and 36 4 ′ respectively. The azimuth of the sun is-42 38',-29 54',-14 37' and 218' respectively.

You didn't say that the building is long, and it is treated as infinite length here. For the convenience of discussion, the 1 meter-high windowsill is taken as the benchmark height of the back building, and the third floor is 7 meters high.

At 9: 00 a.m., the elevation of the sun shading point in the front building is 29 20' (shading).

In the morning 10, the elevation angle of the sun shading point in the front building is 35 30' (shading).

In the morning 1 1, the elevation angle of the shading point in the front building towards the sun is 36 27' (shading, the sun can be seen at the upper part of the window).

In the morning 12, the elevation angle of the shading point of the front building in the sun direction is 37 21'(shading, the sun can be seen from the upper part of the window).

From this point of view, there is insufficient sunshine on the third floor and below, and the shading effect is obvious.