open this link → About Lineweights | AutoCAD 2020 | Autodesk Knowledge Network
it says : lineweight display in paper space change with the zoom factor.
But when I zoom in paper space lineweight does not change. why ?
one is without zoom and other is zoomed however both lineweight appears same
That is because the object in question is in Model Space, seen through a Paper Space Viewport -- it is not in Paper Space. Try drawing something actually out in Paper Space, give it a discernible lineweight, and Zoom in and out to see the difference.
If you have the viewport active and unlocked you probably won't see a lineweight difference. If you lock the viewport or use the pspace command to get in paperspace and then zoom in and out you should see a difference.
