Page 16 - PowerPoint Presentation

2. Go to 5. Go to http://andrewmarsh.com/apps/staging/shading-

http://andrewmarsh.com/apps/staging/sunpath2d.html. Set box.html. Work with the default 3D model in the tool. Set the sun
path diagram as per the location of your city and do the
the sunpath diagram to ‘stereographic’. Set the latitude to following. (2pts)

29N and longitude to 77E and answer the following. (4pts) a. Create at least 2 shading mask diagrams for different

points on the ground. Export the shading mask diagrams
b) Note down the ‘solar time’. Is it different from 3pm? If yes, then why is it different?
Yes, it is different as the solar time is 15:06. An apparent solar day can be 20 seconds shorter or (total 2) and add them here
30 seconds longer than a mean solar day. Long or short days occur in succession, so the
difference builds up until mean time is ahead of apparent time by about 14 minutes near
February 6 and behind apparent time by about 16 minutes near November 3.

c) What is the highest and lowest altitude that the sun reaches at Noon for this latitude?
Highest- 90 degrees
Lowest- 80 degrees

d) What is the sunrise time on winter solstice?
6:41 a.m.

3. Shading mask profile will change at different times of the

day.
a) True
b) False

4. Shadows casted by buildings on the ground always

correlates with the shading mask profile that it generates.
a) True

b) False