Two shafts 'A' and 'B' are made of same material. The shaft 'A' is of diameter D and shaft 'B' is of diameter $$\frac{{\text{D}}}{2}.$$ The strength of shaft 'B' is _________ as that of shaft 'A'

AS WE KNOW THAT STRENGTH OF SHAFT IS MEASURED BY POLOR MODULUS
POLOR MODULUS = J/R
HERE SOLID SHAFT IS GIVEN SO FOR SOLID SHAFT
Pi/16 (D)^3
NOW AS Db =D/2
AND Da=D
So
Pi/16(Db)^3 DIVIDE BY Pi/16(Da)^3
AFTER CANCELATION WE GET
(Db/Da)^3
Put Db=(D/2)^3=D^3/2^3=D^3/8
Now
(D^3/8) /D^3
=1/8