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Question:

Explain the process of generating oscillations in a Wein bridge oscillator

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Question:

a) State the principle of equipartition of energy. Write a relation between number of degrees of freedom, number of particles constituting the system and the total number of constraints. Calculate the degrees of freedom for (i) single atom, (ii) diatomic molecule.

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Question:

Design a universal bias for a class-A CE-amplifier (Fig. 4.11c of your study material) using NPN transistor for the following parameter values: $V_{CC}=20\,\vee ,V_B=4\vee,I_C=10\,mA,V_{BE}=0.6\vee,V_{CE}=10\vee\,$ and $\beta =100.$ Obtain the values of $R_C,R_E,R_1$ and $R_2.$

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Question:

c) Using Maxwell’s relations, prove second energy equation:

$\left ( \frac{\partial U}{\partial p} \right )_T=T\left ( \frac{\partial V}{\partial T} \right )P\left ( \frac{\partial V}{\partial P} \right )T$

Discuss its physical significance.

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Question:

b) Draw Carnot cycle on (i) $P-V,$ and (ii) $T-S$

diagrams. With the help of $P-V$ diagram, show tha

$\frac{Q_1}{Q_2}=\frac{T_1}{T_2},$ where $Q_1$ is the amount of heat absorbed at temperature $T_1$ and $Q_2$ is the amount of heat rejected at temperature $T_2.$

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Question:

a) Explain the statement “entropy of earth-sun system increases” in the light of the principle of increase of entropy.

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Question:

Design a basic band pass filter comprising of a series combination of a T-section high pass filter and a T-section low pass filter to pass the frequencies between 10 kHz and 100 kHz. Take K = 100 for HPF and K = 400 for LPF.

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Question:

c) Write the expressions for the work done for (i) paramagnetic substance, and

(ii) stretched wire. Calculate the work done on the steel wire of length 2.5 m and

area of cross-section $2.5\times 10^{-6}m^{2}$ is suspended from torsion head when a 5 kg weight is suspended at its free end. Take $y=2\times 10^{11}NM^{-2}.$ $y=2\times 10^{11}Nm^{-2}.$

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Question:

Explain the different between a FET and MOSFET on the basis of their construction and working.

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Question:

Using superposition principle obtain the current flowing through load resistor $R_L$ in the circuit shown in Fig. 1.

Image ignouassignments-ignouacademy-com--p-your-94734

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Question:

b) Explain the working of a platinum resistance thermometer with the help of a neat and labelled diagram. State the reasons for using platinum for the construction of a resistance thermometer.

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Question:

a) A reversible process can only be idealised and cannot be achieved in practice. Justify.

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Question:

e) Write an expression for the partition function for an ideal gas made up of N indistinguishable particles. Using this expression, obtain Sackur-Tetrode equation.

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Question:

State, with reasons, whether the following statements are True or False:
i) Kirchoff’s voltage law is valid only for passive element circuits.
ii) In a series resonant circuit, minimum current flows at resonance frequency.
iii) Higher form factor implies better rectification efficiency.
iv) Class A amplifier provides distortion free operation at the cost of efficiency.
v) LC oscillators are not preferred for generating low frequencies.
vi) Operational amplifier is the only type of amplifier available in IC form.
vii) In a regulator IC, the head room should be as large as possible.
viii)It is possible to build any gate using combination of only OR gates.
ix) D-latch uses edge triggering.
x) Mod-7 counter requires 4 flip-flops.

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Question:

The mean speed of oxygen molecules is 450 $ms^{-1}.$

If the radius of an oxygen molecule is 1.8 Å, calculate mean time between two successive collisions and mean free path. Take $n=3\times 10^{25}m^{-3}.$

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Question:

c) A Carnot engine has an efficiency of 40%. Its efficiency is to be raised to 50%. By how much must the temperature of the source be increased if the sink is a $27$ $\,^{\circ}C$ .

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Question:

b) Define adiabatic lapse rate? Obtain an expression for adiabatic lapse rate for earth’s atmosphere?

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Question:

a) A block of metal whose volume expansivity is $5.0\times 10^{-5}\,^{\circ}C^{-5}$ and isothermal compressibility is $1.2\times 10^{-6}$ $atm^{-1}$ has volume 5 litre at 1 atm and $20$ $\,^{\circ}C$ . On applying pressure, its temperature rises by

applying pressure, its temperature rises by $10$ $\,^{\circ}C$ and volume increases by 0.5 $cm^3.$ Calculate the pressure applied.

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Question:

The refractive indices of the core and cladding materials of an optical fibre are 1.51 and 1.39 respectively. Calculate the numerical aperture and light gathering capacity of the fibre.

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Question:

Two energy levels of an atomic system are separated by energy corresponding to frequency $3.0\times10^{14}$ Hz. Assuming that all atoms are in one or the other of these two energy levels, compute the fraction of atoms in the upper energy level at temperature 400 K. Take $k_B=1.38\times10^{23}JK^{34}$ and $h=6.6\times 10^{-34}$ Js