Radius of nucleus (R) having mass number (A) is given as, R=R0A1∕3 where, R0 is constant. Taking log both side, we have lnR=lnR0A1∕3 ⇒lnR=lnR0+lnA1∕3 ⇒lnR=lnR0+
1
3
lnA ⇒lnR=
1
3
lnA+lnR0 this is in the form of equation of straight line y=mx+c where, y=lnR m=