WHEN PPL HAVE NO STRONG ARGUMENTS THEY GO OVER WITH WHTEVER FUSSY THEY HAVE AND JUST KEEP ON SINGING IT..... SAME IS THE CASE WITH U AMANGEM.... U MADE A CRAP OF THAT QUES. BY SAYING THAT ELECTRIC FUSE AND LAMP SHUD ALSO MATCH WITH THERMAL EXPANSION... THE DEVICES HAVE TO BE MATCHED WITH THEIR FUNCTIONING PRINCIPLES AND NOT WITH THEIR PROPERTIES.... DONT KNOW WHY U WANT TO PROVE ME WRONG.. WHEN U URSELF DONT KNOW WHT U R SAYING.... U R JUST SOUNDING KIDDISH IN THAT SCENCE OF U...