3.12.6　Analysis and questions

(1)Why can we measure the diameter rather than the radius of Newton’s rings in the experiment?

(2)Does the transmitted light from Newton’s rings can form the interference fringes?What’s the difference between it and the interference fringes from reflected light?Why?(https://www.daowen.com)

(3)If there is a tiny bump on the plate glass at the bottom of Newton’s rings,what will happen to the interference fringes?