Hey, here how I like to think about it: ds/t starts with a line intergral, meaning we have to go around the entire boundary created by the centerline running through the thickness. ds is the length of this centerline, and t is the thickness corresponding to where that length is taken from. Lets look at our example, isolating the 60mm side. ds will be 60-2(3/2) mm. The thickness of that 60 mm segment is 5 mm. So we have ds/t = (57/5). Since we have two of these sides, we must multiply it by 2. We repeat a similar process with the top 40 mm segment, which gives (35/3) then once again that repeats in the section, so we multiply by 2. That leaves us with [2(57/5)+2(35/3)]. Hope this helps!
Problem begins at 3:30. Once again, thanks for all the recent support!
Why ds/t is [2(57/5)+2(35/3)]🙏🙏
Hey, here how I like to think about it:
ds/t starts with a line intergral, meaning we have to go around the entire boundary created by the centerline running through the thickness. ds is the length of this centerline, and t is the thickness corresponding to where that length is taken from.
Lets look at our example, isolating the 60mm side. ds will be 60-2(3/2) mm. The thickness of that 60 mm segment is 5 mm. So we have ds/t = (57/5). Since we have two of these sides, we must multiply it by 2. We repeat a similar process with the top 40 mm segment, which gives (35/3) then once again that repeats in the section, so we multiply by 2. That leaves us with [2(57/5)+2(35/3)].
Hope this helps!