Question

Find skin depth of 5GHz for silver with a conductivity 6.1×10^7s/m and relative permittivity 1.

(a) 0.00091m

(b) 0.9113μm

(c) 0.319μm

(d) 0.1913μm

I had been asked this question in a job interview.

The above asked question is from Radiation in division Radiation, Baluns & Polarization of Antennas

Answer 1

Right option is (b) 0.9113μm

The explanation: The skin depth is given by \(δ = \sqrt{\frac{1}{\pi fμσ}}\)

Given f=5GHz

Conductivity σ= 6.1×10^7 s/m

And μr = 1 =>μ=4π ×10^-7

⇨ \(δ = \sqrt{\frac{1}{\pi fμσ}}=0.9113\mu m.\)