Q1
mcq
Which one of the following is the natural nanomaterial ?
- A. Grain of sand
- B. Peacock feather
- C. Skin of the whale
- D. Peacock beak
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Q2
mcq
In an electron microscope, the electrons are accelerated by a voltage of 14 kV. If the voltage is changed to 224 kV, then the de-Broglie wavelength associated with the electrons would :
- A. decrease by 4 times
- B. increase by 2 times
- C. increase by 4 times
- D. decrease by 2 times
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Q3
mcq
The variation of frequency of carrier wave with respect to the instantaneous amplitude of the modulating signal is called :
- A. Phase modulation
- B. Amplitude modulation
- C. Pulse width modulation
- D. Frequency modulation
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Q4
mcq
Q factor is equal to __________.
- A. $\frac{1}{R}\sqrt{\frac{L}{C}}$
- B. $\frac{1}{R}\sqrt{\frac{L}{C}}$
- C. $\frac{X_L}{R}$
- D. All the above
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Q5
mcq
Two metallic spheres of radii 1 cm and 3 cm are given charges of $-1 \times 10^{-2}$ C and $5 \times 10^{-2}$ C respectively. If these are connected by a conducting wire, the final charge on the bigger sphere is :
- A. $1 \times 10^{-2}$ C
- B. $3 \times 10^{-2}$ C
- C. $2 \times 10^{-2}$ C
- D. $4 \times 10^{-2}$ C
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Q6
mcq
Which of the following is an electromagnetic wave ?
- A. $\beta$-rays
- B. $\gamma$-rays
- C. $\alpha$-rays
- D. All of the above
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Q7
mcq
An air bubble in glass slab of refractive index 1.5 (near normal incidence) is 5 cm deep when viewed from one surface and 3 cm deep when viewed from the opposite face. The thickness of the slab is :
- A. 12 cm
- B. 8 cm
- C. 16 cm
- D. 10 cm
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Q8
mcq
In India electricity is supplied for domestic use at 220 V. It is supplied at 110 V in USA. If the resistance of a 60 W bulb for use in India is R, the resistance of a 60 W bulb for use in USA will be :
- A. R/4
- B. R
- C. R/2
- D. 2R
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Q9
mcq
A wire of length $l$ carrying a current $I$ along the Y direction is kept in a magnetic field given by $\vec{B} = \beta(i + j + k)$. The magnitude of Lorentz force acting on the wire is :
- A. $\sqrt{2} Il\beta$
- B. $\frac{I}{3}l\beta$
- C. $\frac{1}{2}Il\beta$
- D. $\frac{1}{3}Il\beta$
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Q10
mcq
Emission of electrons by the absorption of heat energy is called __________ emission.
- A. Thermionic
- B. Photo electric
- C. Secondary
- D. Field
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Q11
mcq
If a current of 7.5 A is maintained in a wire for 45 seconds then the charge flowing through the wire is :
- A. 6 C
- B. 365.5 C
- C. 3 C
- D. 337.5 C
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Q12
mcq
The charge of cathode ray is :
- A. neutral
- B. positive
- C. not defined
- D. negative
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Q13
mcq
A step-down transformer reduces the supply voltage from 220 V to 11 V and increases the current from 6 A to 100 A. Then its efficiency is :
- A. 0.12
- B. 1.2
- C. 0.9
- D. 0.83
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Q14
mcq
The electric potential of an electron is given by $V = V_0 \ln(\frac{r}{r_0})$, where $r_0$ is a constant. If Bohr atom model is valid, then variation of radius of $n^{th}$ orbit $r_n$ with the principal quantum number $n$ is :
- A. $r_n \propto \frac{1}{n^2}$
- B. $r_n \propto \frac{1}{n}$
- C. $r_n \propto n^2$
- D. $r_n \propto n$
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Q15
mcq
Transverse nature of light is shown in :
- A. scattering
- B. interference
- C. polarisation
- D. diffraction
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Q17
short answer
2 marks
How will you increase the current sensitivity of a galvanometer ?
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Q18
short answer
2 marks
Define work function of a metal. Mention its unit.
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Q19
short answer
2 marks
Calculate the radius of ${}^{197}_{79}\text{Au}$ nucleus.
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Q24
short answer
3 marks
The angle of minimum deviation for the equilateral prism is $40^\circ$. Find the refractive index of the material of the prism.
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Q25
long answer
3 marks
Derive the relation between f and R for a spherical mirror.
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Q26
long answer
3 marks
Obtain a relation between current and drift velocity.
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Q27
long answer
3 marks
List out the laws of photo electric effect.
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Q28
long answer
3 marks
Draw the circuit diagram of NPN transistor in Common Emitter Configuration.
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Q30
long answer
Derive the expression for resultant capacitance, when capacitors are connected in series.
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Q31
long answer
Find the:
(i) Angular momentum
(ii) Velocity of the electron revolving in the 5th orbit of hydrogen atom.
($h=6.6 \times 10^{-34}$ Js ; $m=9.1 \times 10^{-31}$ kg)
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Q32
short answer
List out salient features of magnetic Lorentz force.
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Q33
long answer
Find the impedance of a series RLC circuit, if the inductive reactance, capacitive reactance and resistance are 184 $\Omega$, 144 $\Omega$ and 30 $\Omega$ respectively. Also calculate the phase angle between voltage and current.
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Q34
long answer
5 marks
(a) Explain the construction and working of full wave rectifier.
OR
(b) Explain the construction and working of transformer.
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Q35
long answer
5 marks
(a) Derive an expression for electrostatic potential due to an electric dipole.
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Q36
short answer
Find the Angular momentum of the electron revolving in the 5th orbit of hydrogen atom. ($h=6.6×10^{-34} Js ; m=9.1×10^{-31} kg$)
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Q37
long answer
5 marks
(a) Derive an expression for electrostatic potential due to an electric dipole. OR (b) Obtain the equation for bandwidth in Young’s Double Slit Experiment.
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Q38
long answer
5 marks
(a) Using Biot-Savart Law deduce the relation for the magnetic field at a point due to an infinitely long straight conductor carrying current. OR (b) Discuss the spectral series of hydrogen atom.
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Q39
long answer
5 marks
(a)(i) How do we obtain characteristic X-ray spectra ? (ii) Calculate the cut-off wavelength and cut-off frequency of X-rays from an X-ray tube of accelerating potential 20,000 V. OR (b) What is spectrum ? Explain the types of emission spectrum.
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Q40
long answer
5 marks
(a) Obtain Lens maker’s formula. OR (b) Explain the determination of the internal resistance of cell using voltmeter.
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Q41
long answer
(a) Explain the construction and working of full wave rectifier.
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Q42
long answer
(b) Explain the construction and working of transformer.
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Q43
long answer
(b) Obtain the equation for bandwidth in Young’s Double Slit Experiment.
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Q44
long answer
(a) Using Biot-Savart Law deduce the relation for the magnetic field at a point due to an infinitely long straight conductor carrying current.
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Q45
long answer
(b) Discuss the spectral series of hydrogen atom.
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Q46
short answer
How do we obtain characteristic X-ray spectra ?
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Q47
short answer
Calculate the cut-off wavelength and cut-off frequency of X-rays from an X-ray tube of accelerating potential 20,000 V.
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Q48
long answer
(b) What is spectrum ? Explain the types of emission spectrum.
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Q50
long answer
(b) Explain the determination of the internal resistance of cell using voltmeter.
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