The pitch of a screw gauge is 0.5mm and there are 100 divisions on circular scale.The instrument reads +2 circular divisions when nothing is put in between its jaws.In measuring the diameter of a wire, there are 8 divisions on the main scale and 83rd circular scale division coincide with the reference line.Then the diameter of wire is

Question

samigupta8 · Answer

@parthkohli

samigupta8 · Answer

I m getting a diff ans then theirs...

samigupta8 · Answer

@priyar

samigupta8 · Answer

My ans is 8.405 mm and they have given it as 4.405..
I don't know how they got that?

samigupta8 · Answer

@imqwerty

imqwerty · Answer

least count = pitch/(no. of divisions)

total reading = main scale reading  + (corrected circular scale reading x least count) 
                     $8+\left[\left(83-2) \right) \times 0.005 \right]$ 
                      =8.405

samigupta8 · Answer

That's my ans even...bt they have given something else..

imqwerty · Answer

their answer is wrong :)

priyar · Answer

Yes your answer is correct! @samigupta8