how many resistance commbinations are possiable with

      1.  n equal resistances.

      2.  n unequal resistance.

similarly

      what would be the effective resistance of any simple circuit having a sphere

       (of resistivity  , a diameter of 2 cm) ,a simple resistance of 3 ohm

and a cell with negligible internal resistance.

for the first par thee are n different ways of arranging n equal resistances...how....series,one pair in parallel with (n-2) in series,3 in parallel with (n-3) in series,................n in parallel

 

for the second part each of the above ooptions can be arranged further in 0,nC2,nC3.......nC(n-1),0...

 

for the second part please post the ques again...only one ques can be askd at atime