The galvanometer shown in the circuit has a resistance of 5 Ω. Find the current through the galvanometer using Thevenin’s theorem.
Fig.22(a)
Equivalent resistance of the circuit \(R_{th}=\frac{10\times15}{10+15}+\frac{12\times16}{12+16}=6+6.86=12.86\ \mathrm{\Omega}\)
Total current follow through the circuit \(I=\frac{10}{12.86}=0.78\ Amp\).
The current passing through the branch resistances \(12\ \mathrm{\Omega}\) and \(16\ \mathrm{\Omega}\) is \(I_1=\frac{10}{28}=0.357\ Amp\).
The current passing through the branch resistances \(10\ \mathrm{\Omega}\) and \(15\ \mathrm{\Omega}\) is \(I_2=\frac{10}{25}=0.4\ Amp\).
\(V_x=10-12\times0.36=10-4.286=5.714\ Amp\).
And \(V_y=10-0.4\times10=10-4=6\ V\)
Hence \(V_{o.c}=V_y-V_x=6-5.714=0.286\ V\)
Fig. 22(b)
Fig. (c)
Fig. 22(d)
Here the galvanometer resistance \(R=5\ \mathrm{\Omega}\)
The current through the galvanometer is \(I_L=\frac{V_{o.c}}{R_{th}+R}=\frac{0.286}{12.86+5}=0.016\ Amp\).
Find the current in each branch of the network using Kirchhoff’s law
Fig.23
Distinguish between group velocity and phase velocity.
Write short notes on
Derive the expression for overall noise figure of a cascaded system.
What is meant by entropy of a source?