(a) Explain briefly dielectric strength.

(b) An electromagnetic wave has its wavelength shorter than those of radiowave and microwave but longer than that of visible light.

(i) Identify the wave.

(ii) Name one suitable detector for the wave.

(iii) Name one source of the wave.

(c) An oil drop carrying a charge of 1.0 x 10\(^{-19 }\)C is found to remain at rest in a uniform electric field of intensity 1200 NC\(^{-1}\). Calculate the weight of the oil drop.

(d) An RLC series circuit consists of a 100\(\Omega\) resistor, 0.05 H inductor and a 25 \(\mu\) capacitor. A 220 V, 50 Hz mains voltage is applied across the circuit. Calculate the:

(i) impedance;

(ii) current. (\(\pi\) = 3.14)