21.) List 3 factors that influence sheet size selection.?
1- the clarity of drawing details (more clarity needs larger size) 2- the complexity of the drawing (more complexity needs larger size) 3- the target audience (workshop drawing: small size - construction drawing: large size)
If a wire is stretched to double its length, what will its new resistance be?
What happens to the resistancece of the wire when the length is doubled?Since the length of the wire is doubled, its area of cross-section is halved so as to keep the volume of the wire constant.Now the resistance of the wire is proportional to length of the wire, since the length of the wire is doubled its resistance also doubles due to doubling of the length. But resistance is also inversely proportional to the area of cross-section, and as area of cross-section is halved due to doubling of length, the resistance is once more doubled due to the halfing of the area of cross-section. So overall the resistance of the wire becomes four times the original resistance.
If I have a floor plan in my hands on an A3 size paper, but the scale mentions that it was originally made on an A1 size paper. How should I factor in the change in paper size when I measure the area on the A3 print out?
In short, there is no exact answer to this, because it depends on a number of things, particularly whether you want to resulting document to be accurate.It’s not the size of the sheet that might be important, it might be the size of the drawing itself.If accuracy isn’t a problem, use a factor of 2 and don’t worry about it.If it is, things become more complicated.Your question assumes that the original has been printed true to scale. In many cases it’s not!If it has been printed on paper directly from a CAD package and the print has been configured correctly, and there have been no ‘scale to fit’ page options checked, it should be true to scale.If it has been printed from CAD to PDF, then it may well not be correct, because printer margins vary from one device to another, and if the original document had smaller margins than your device can support, your PDF print dialog will offer a print to fit option by default.Planning Authorities have this problem frequently when printing files submitted electronically. I’ve had to go through an exercise of printing them myself to prove that they overlay precisely and that the boundaries and areas are accurate.If your original itself has been copied, you may find that inaccuracies have crept in there.In short, you simply can’t assume that your original drawing is true to scale. This is why architects often use scale bars on their drawings. Some don’t deliberately as a means of making it more difficult for people to make unauthorised use of them.The most reliable way to do this is to scale something with a known or fixed dimension (the longer the better), and work out the enlargement or reduction factor.