Derive an expression for lifting power of a magnet
Consider two poles arranged directly opposite each other as shown in Fig. 29. Let each have an area A square meters and F Newtons be the force of alteration between them. Let one pole be moved by an incremental distance \(\delta x\) against the force Fj then the work done is obviously F\(\delta x\) Juoules.
The volume of the magnetic field between the poles is increased by A\(\delta x\)m3
Fig.29
Hence the energy stored increased by
Energy density of the magnetic field \(\times\)A\(\delta x\) Joules
Or \(F\delta x=\frac{1}{2}\left(\frac{B^2A}{\mu_0\mu}\delta x\right)Joules\)
Energy is stored in the air gap.
Hence \(\mu=1\)
\(F=\frac{B^2A}{{2\mu}_0}\)
Find VAB from the circuit if all the resistances are of same value of 1 Ω.
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Fig. 20(a)
Draw a mathematical expression for RMS value of a sinusoidal voltage \(v=V_{m}\sin{{\omega t}}\).
Compare electric and magnetic circuits with respect to their similarity and dissimilarities.
What is Carson’s rule? Explain it.
Write a short note on TDM (Time Division Multiplexing).
Compare PAM, PWM and PPM
Write a short note on Bathe hole coupler.
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Fig. 18(a)