A capacitor is made of two circular plates each of radius \(12~\text{cm}\) and separated by \(5.0~\text{cm}\). The capacitor is being charged by an external source. The charging current is constant and equal to \(0.15~\text{A}\). The displacement current across the plates is:
1. \(0\)
2. \(0.14~\text{A}\)
3. \(0.16~\text{A}\)
4. \(0.15~\text{A}\)

A parallel plate capacitor is made of circular plates each of radius \(R=6.0~\text{cm}\) has a capacitance \(C=100~\text{pF}.\) The capacitor is connected to a \(230~\text V\) AC supply with an (angular) frequency of \(300~\text{rad/s}.\) The amplitude of \(\vec{B}\) at the point \(3~\text{cm}\) from the axis between the plate is:

       
1. \(1.12\times 10^{-11}~\text T\)
2. \(2.01\times 10^{-12}~\text T\)
3. \(1.63\times 10^{-11}~\text T\)
4. \(1.01\times 10^{-12}~\text T\)

A radio can tune in to any station in the \(7.5\) MHz to \(12\) MHz bands. What is the corresponding wavelength band?
1. \(40\) to \(25\) m
2. \(10\) to \(100\) m
3. \(50\) to \(60\) m
4. \(20\) to \(10\) m

The amplitude of the magnetic field part of a harmonic electromagnetic wave in a vacuum is \(B_0=510~\text{nT}\). What is the amplitude of the electric field part of the wave?
1. \(200~\text{N/C}\)
2. \(153~\text{N/C}\)
3. \(150~\text{N/C}\)
4. \(510~\text{N/C}\)

Suppose that the electric field amplitude of an electromagnetic wave is \(E_0 = 120~\text{N/C}\) and that its frequency is \(\nu = 50.0~\text{MHz}.\)$$$$ The value of propagation constant \(k\) is:
1. \(2.01~\text{rad/m}\)
2. \(1.72~\text{rad/m}\)
3. \(1.05~\text{rad/m}\)
4. \(2.41~\text{rad/m}\)

In a plane electromagnetic wave, the electric field oscillates sinusoidally at a frequency of $\mathrm{}$\(2.0\times 10^{10}~\text{Hz}\) and amplitude \(48~\text{V/m}\). What is the amplitude of the oscillating magnetic field?
1. \(4.2\times 10^{-8}~\text{T}\)
2. \(2.4\times 10^{-7}~\text{T}\)
3. \(3.8\times 10^{-8}~\text{T}\)
4. \(1.6\times 10^{-7}~\text{T}\)

The electric field part of an electromagnetic wave in vacuum is,
\(\vec{E}=(3.1~\text{N/C}) \cos \left[(1.8~\text{rad/m}) y+\left(5.4 \times 10^8 ~\text{rad/s}\right)t\right] \hat{i}.\)
What is the frequency of the wave?
1. \(5.7\times 10^{7}~\text{Hz}\)
2. \(9.3\times 10^{7}~\text{Hz}\)
3. \(8.6\times 10^{7}~\text{Hz}\)
4. \(7.5\times 10^{7}~\text{Hz}\)