Hello friends ! I'm new here and i have this question. i don't know how this Example solved!! r is radius and radius is half of diameter right? so what does 12 had to do with it?
In GMD section why distance is 23.5?? how did it got 0.5??

 

There is another example that found (r) and again what does 12 had to do with it?
And also in GMD part , the distance is 44 why it's 45.6???!!!!!!

 

And another One!!! can't believe this!!

 

How many inches are there in a foot?

If the authors of any of those diagrams had properly tracked units, this would have been apparent.

More to the point, if you DON'T start tracking your units, you would do a calculation like this and be off by a significant factor and never know the difference. If it turned out to be something life critical, you might not find out until you are being charged with criminally negligent homicide.

 

How many inches are there in a foot?

If the authors of any of those diagrams had properly tracked units, this would have been apparent.

More to the point, if you DON'T start tracking your units, you would do a calculation like this and be off by a significant factor and never know the difference. If it turned out to be something life critical, you might not find out until you are being charged with criminally negligent homicide.

Thanks man. it's because in my country we use The metric system i'm not familiar with the american units !
also , do you know anything about how the distance between 2 bundles found 23.5 while it's actually 23

 

Thanks man. it's because in my country we use The metric system i'm not familiar with the american units !

The need to track units is independent of whether you use the metric or the English system. What if the formulas had been set up to use dimensions in cm but some had been given in m? Then you would have had this strange factor of 100 in the author's solution for no apparent reason. It might have been easier for you to figure it out, but it still would have been very easy for you to work the problem and miss the need for that factor.

also , do you know anything about how the distance between 2 bundles found 23.5 while it's actually 23

The distance between conductors is given as "23 feet 6 inches". There are 12 inches in a foot, so 6 inches is 0.5 feet. Hence the total is 23 ft + 0.5 ft = 23.5 ft.

 

The need to track units is independent of whether you use the metric or the English system. What if the formulas had been set up to use dimensions in cm but some had been given in m? Then you would have had this strange factor of 100 in the author's solution for no apparent reason. It might have been easier for you to figure it out, but it still would have been very easy for you to work the problem and miss the need for that factor.



The distance between conductors is given as "23 feet 6 inches". There are 12 inches in a foot, so 6 inches is 0.5 feet. Hence the total is 23 ft + 0.5 ft = 23.5 ft.

Thanks alot ! i was off today !! sue me ! )

 

If you aren't familiar with a measurement system, then it is easy to miss that something written like "23 feet 6 inches" means that you have to add the two dimensions together to get the actual dimension. I can't think of a comparable situation in the metric system where something would be written like "10 m 50 cm".