2. A sample of N type semiconductor has an electron density of 6.25 x 1018/cm3 at 300 K. If intrinsic concentration of carriers in this sample is 2.5 x 1013/cm3 at this temperature, the hole density is
5. Two coaxial metallic cylinders have radii R1 and R2. The space between them is filled with a dielectric having dielectric constant ?r. The capacitance per metre length is
9. A parallel plate capacitor has area of plate equal to 1 m and distance between plates is also 1 m2. The lossy dielectric has a complex dielectric constant ?r = ?'r - j ?"r. If the capacitor is represented by R and C is parallel, then
