# A cylindrical capacitor has two co-axial cylinders of length $15\; cm$ and radii $1.5\; cm$ and $1.4\; cm$. The outer cylinder is earthed and the inner cylinder is given a charge of $3.5 \mu C$. Determine the capacitance of the system and the potential of the inner cylinder. Neglect end effects (i.e., bending of field lines at the ends).

$(B) 2.92 \times 10^{4} V$