Lx» © To mesure the diameter of «smal pherical/oindical body wsng veer ) Le PARATUS AND MATERIAL REQUIRED \emier Calipers spherical body (a pendulum bob or a glass mabe) ora smal (i liner, Ltacony 1k Vernier constant =1 MSD —1.VSD Magne ofthe smallest main scale division or Vernier constant =‘hays 2 vst CMS te iene a ne Lrociovs 1 Eeamiehe ein of ‘ er calipers he vernie scale mt sing ameothy over the main sce ap mac Uppese, stant of the vem ealpes. Reel 1 Bring the movable fs RE cle clack wih he fs jaes AC Obmeve wheter the revo of Sema Esak Shines withthe zea fain sal thin st sn oe the divishon on the veer SOL IRa gins with division onthe ra sae, Rew! the vo ero wth a proper poate cr pogatine gh Repeat lt hte tims and lad the maa re ctor and hence set cere Te Cis hee ne sera von eon al 2 Determine the vere, epi in the bservatons 4 Te messe the diame of the small phere, bit ery te without any inde pressure inbetween the lover jas snd Basson i Fig 29, The aws sdb pert peepee hs chameter ating meant Gani hte th screw § tm clamp Uh je te dy 5 Nove the main scale alvin st the la the zero of the NeeRctaake. Recon the verlet scale ison tht evinces sith some main wale dissin. Thc mnt he courte oes on ce ofthe semier sale They lve diameters Nea VEL 5 Rotate the pervs fa ty poston thug Aso that diame 2 6 peepee othe awe Proceting a in sep 5, note Ie mln sete rang and the Semi scale eset ant fe he thservet diameter Mt 7. Measure the dames sith of the spe ral Ain to mutually perpendicular ditetions or atest to mare er, Reco al the servations In the tabular frm. Find the mean observed dhametet, Apply 2er0 ‘rection to pet the mean coreced diameter Expresate result in suitable unite wits ata ume of sagitcant Figures Losseavations ano carcuLations ‘AcTor vemier constant 1 main scale division (MSD) = 1 mm ~0.1 em IWYS0 =9 MSD ysp-2Msp 1ys0-3 Veer comtant= 1MSD -1 VSD =1 MSD- 2 s150-= 1 =O mm =001 emDenvorne 44 NC oy i) em Om we 0 eae ype ld Mea ren eton fe) a eee Moan ror omni = spheres he sm To mossure the dlameter he ov iameter ofthe small sphere/evlinder a a aor dr peipendicular damete ‘Observed diameter [es eg ane oo? | ek an pedi erate sae non [we | Marte | uae | uae | ay PPE ye 2 i atm | te ton rT] | Ls L BaP Namatrere tater (fy)=2LEE Pa ee Mean cored damett =D, 4(29= om [eesuir Diameter ofthe given sphemeylinder = em 1 Neer sl ie sy oe tema seat not 9 aply machine ofa, ‘cnr should be carefully determined and recosded. 2 The serie vnsant and ze 23. The ody should be jrippe! gen between the jaws without any undue pressure, + To avoid any eror due to parallax, the eye should he hept directly over the verier division being observed 5. The readings for diameter at each position must be noted in two mutually perpendicular directions, 6 Each observation should be recorded with correct significant figures and units, oer 1 Te jv oft vem pers yal be perpendear a he sn ele 2 Mewonsrank nm teins 2. Theseus ney eee The 20 ert hinmen uy have Ben en nt aecune 5 Foon err do nadine neg he cerns malt te re a reEXPERIMENT Lou & To measure the diameter ofa given wire using a serew gouge and to find its volume, Screw gauge a thin metal: wite and & met sete 1 Pia Distance moved by the screw othe ar se Nube ono aula cle Feet Total quam of divisins. the ica wal & To eading = LS + CSR» Least cut = M+ Least cin 4 Volume o the wine=net=n( 2) Loncram 7.27 Measig ant of wegen gg Leroccoure 1 First check thatthe rachetR on the head ofthe screw is functioning propedy “To find the pitch 2 Note the value of one small division on the linear scale. Gis our cpr rans at de nt eh ding nth 5. Calculate pitch ofthe screw as follows : _ Distance moved by thereon thee ele ‘Pach =" Numb of rotations ofthe creuarsele— °% P~ BsusTo find the least count ‘6 Note the total mamber of divisions the cela sae then Tia number of dvsions on the eur ake Toi the nro ero 7 Bing the std and the screw ofthe screw gauge i cnt with each eter (0) I the zero mark ofthe ccular cle cies withthe reference ine then record the 20 (0) he ero mark ofthe crculr sae divisions teow the reerence ine (a, ond, ed, ‘etn ef i rr pa cans eth oe nes keh on ear pe the Zev mask of the icles fs vino lave the reference ine i, 9th 8h {78 Fc division of Ue cca scale cnc with he relerence ie) then he 29 Fe Zen wees ample divsiom canes with the rere ie then ‘measure diameter ofthe thin wire - ‘ ick and inst the wite bene the sree ar he stud. Mave the senew forward sng the rachel the we nd the Hinge state sipping over the exp. 5 Note the lncar scale reading UM) and dhe numberof division ofthe cieular sale hat eoindes withthe eerence ise. Then find the obwerved diameter a a =LSR + CSR =M e wae 10. The wire may not have uniform area of cross-section. To make comrecion for rotate the wie steough 9° by holding itn same postion asim sep 9 Fd the diameter Bo he wie i he perpendicular position, as shown im Tig, 39. Mh The wire may not be exacly cylindrical. To make cretion for ‘ove measure dlameter ofthe ite tn wo) mutually perpendicular lectins at fae more places along the length ofthe wie 12 Take the mean of the diferent values of diameters 50 obtained. ‘Add sero correction, if any, with Proper sign get the comected alte ofthe diameter of the wie. “To measure length of the wire 1. Straighten the wire by removing kinks, if any, fom it |. Sertch the wite along the length of a metre scale, Read the ‘between the readings gives the length of the iran id mea emg) ofthe wieLorstavanions ‘Aor pitch and east count Linear ditance menedbythesre" gg. poem PAC ro tne en tila Se ae 1. For zero conection | soko circult scale esbeow/sbowe the refereeing, | ao roe 603 i est cd 1 prope gn of mo era C For mesroremen of ameter ofthe wie Length ofthe wire (y= ean Mean length, 1th“ |nw CANCE om! The diameter of the given wire ax meumered ley were gauge = ih The volume of thir given wire «___ cm? Jhet and nit Frode the cap seas to avoid 2. Thesscrew must alway be rutated by holeling it fram: any undue presstine« as-soan as the rachet starts producing clicking sound. oper sigh and taken into account. If these is the sre a stopp any. should be noted carefully with W shoud be recorded as mil st lash ero the serew sould always (nthe same direction while making the 6. The diameter of the wire should be measured in twin mally perpendicular directions # five dittrent places along the length of the wie View all the rewings keeping the eye pespenndicular to the scale to avo wero cue to paral, A. Belore measuring the length af the wire, remave the kinks in it if any. [sources oF ERaon 1. The cross-section af the wire may not be uniform, 2. Error due to backlash though minimised but cannot be completely eliminated 2. The graduations on the finwar scale and the circular scale may not be evenly marked. the rachet arrangement és sot functioning properly, the nelie pressure on the wire may charge its diameter wa te we