Q1
mcq
The principle based on which a solar cell operates is :
- A. Photovoltaic action
- B. Diffusion
- C. Carrier flow
- D. Recombination
Solution hidden
Log in to view solution →
Q2
mcq
If the amplitude of the magnetic field is $3\times10^{-6}$ T, then the amplitude of the electric field for a electromagnetic wave is :
- A. $600\ Vm^{-1}$
- B. $100\ Vm^{-1}$
- C. $900\ Vm^{-1}$
- D. $300\ Vm^{-1}$
Solution hidden
Log in to view solution →
Q3
mcq
A toaster operating at 240 V has resistance of 120 $\Omega$. Its power is :
- A. 240 W
- B. 400 W
- C. 480 W
- D. 2 W
Solution hidden
Log in to view solution →
Q4
mcq
Atomic number of H - like atom with ionization potential 122.4 V for n=1 is :
- A. 3
- B. 4
- C. 2
- D. 1
Solution hidden
Log in to view solution →
Q5
mcq
The transverse nature of light is shown in :
- A. scattering
- B. interference
- C. polarisation
- D. diffraction
Solution hidden
Log in to view solution →
Q6
mcq
In an oscillating LC circuit, the maximum charge on the capacitor is Q. The charge on the capacitor when the energy is stored equally between the electric and magnetic field is :
- A. Q/2
- B. Q/2
- C. Q
- D. Q/3
Solution hidden
Log in to view solution →
Q7
mcq
A bar magnet of length ‘l’ and magnetic moment ‘P_m’ is bent in the form of an arc as shown in figure. The new magnetic dipole moment will be :
- A. m^2 P/\pi
- B. P_m
- C. m^1 P^2
- D. m^3 P/\pi
Solution hidden
Log in to view solution →
Q8
mcq
The speed of light in an isotropic medium depends on :
- A. the nature of propagation
- B. its intensity
- C. the motion of the source w.r.t. medium
- D. its wavelength
Solution hidden
Log in to view solution →
Q9
mcq
In a series RL circuit, the resistance and inductive reactance are the same. Then the phase difference between voltage and current in the circuit is :
- A. \pi/6
- B. \pi/4
- C. Zero
- D. \pi/2
Solution hidden
Log in to view solution →
Q10
mcq
Two identical conducting balls having positive charges q_1 and q_2 are separated by a center to center distance ‘r’. If they are made to touch each other and then separated to the same distance, the force between them will be :
- A. more than before
- B. less than before
- C. zero
- D. same as before
Solution hidden
Log in to view solution →
Q11
mcq
Three capacitors are connected in triangle as shown in figure. The equivalent capacitance between the points A and C is :
- A. 4 \mu F
- B. 2 \mu F
- C. 8 \mu F
- D. 6 \mu F
Solution hidden
Log in to view solution →
Q12
mcq
The threshold wavelength for a metal surface whose photoelectric work function is 3.313 eV :
- A. 6000 Å
- B. 4125 Å
- C. 2062.5 Å
- D. 3750 Å
Solution hidden
Log in to view solution →
Q13
mcq
Light transmitted by Nicol prism is :
- A. plane polarised
- B. partially polarised
- C. elliptically polarised
- D. unpolarised
Solution hidden
Log in to view solution →
Q14
mcq
The gravitational waves were theoretically proposed by :
- A. Albert Einstein
- B. Conrod Rontgen
- C. Edward Purcell
- D. Marie Curie
Solution hidden
Log in to view solution →
Q15
mcq
The value of forbidden energy gap for Si at room temperature is :
- A. 1.1 V
- B. 0.7 eV
- C. 1.1 eV
- D. 0.7 V
Solution hidden
Log in to view solution →
Q19
short answer
A straight metal wire crosses a magnetic field of flux 4 mWb in a time 0.4 sec. Find the magnitude of the emf induced in the wire.
Solution hidden
Log in to view solution →
Q20
short answer
State the applications of Seebeck Effect.
Solution hidden
Log in to view solution →
Q21
short answer
The half-life of radioactive sample is 5.01 days. Calculate the decay constant.
Solution hidden
Log in to view solution →
Q23
short answer
What is meant by biasing ? Mention its types.
Solution hidden
Log in to view solution →
Q24
short answer
If the focal length is 150 cm for a lens, what is the power of the lens ?
Solution hidden
Log in to view solution →
Q25
long answer
Discuss the Beta 1 (β 1 ) decay process with an example.
Solution hidden
Log in to view solution →
Q26
long answer
A copper wire of cross-sectional area 0.5 mm 2 carries a current of 0.2 A. If the free electron density of copper wire is 8.4×10 28 m −3 , then compute the drift velocity of free electron.
Solution hidden
Log in to view solution →
Q27
long answer
Derive the equation for effective focal length for lenses in contact.
Solution hidden
Log in to view solution →
Q28
long answer
Define current sensitivity. State the factors which increase the current sensitivity of a galvanometer.
Solution hidden
Log in to view solution →
Q29
long answer
How many photons per second emanate from a 50 mW laser of 640 nm ?
Solution hidden
Log in to view solution →
Q30
long answer
Derive the equation for inductance of a solenoid. Assume that the length of the solenoid is greater than its diameter.
Solution hidden
Log in to view solution →
Q31
long answer
What are the differences between interference and diffraction ?
Solution hidden
Log in to view solution →
Q33
long answer
Determine the wavelength of the light emitted from LED, which is made up of GaAsP semiconductor, whose forbidden energy gap is 1.875 eV. Mention the colour of the light emitted (Given h=6.6×10 −34 Js).
Solution hidden
Log in to view solution →
Q34
long answer
Explain about simple microscope and obtain equation fo
Solution hidden
Log in to view solution →
Q35
long answer
Explain about simple microscope and obtain equation for magnification for near point focusing and normal focusing.
Solution hidden
Log in to view solution →
Q36
long answer
Explain the determination of unknown resistance using metre bridge.
Solution hidden
Log in to view solution →
Q37
long answer
Calculate the magnetic field produced at a point along the axis of the current carrying circular coil. Write down the equation of the magnetic field at the center of the coil using Biot-Savart law.
Solution hidden
Log in to view solution →
Q38
long answer
Derive the equation for angle of deviation produced by a prism and thus obtain the equation for refractive index of material of the prism.
Solution hidden
Log in to view solution →
Q39
long answer
Obtain Einstein’s photoelectric equation with necessary explanations.
Solution hidden
Log in to view solution →
Q40
long answer
Find out the phase relationship between the voltage and current in a pure inductive circuit. Draw the phasor and wave diagrams.
Solution hidden
Log in to view solution →
Q41
long answer
List out the advantages and limitations of frequency modulation.
Solution hidden
Log in to view solution →
Q42
long answer
Explain the Maxwell’s modification of Ampere’s circuital law.
Solution hidden
Log in to view solution →
Q43
long answer
Calculate the electric field due to a dipole at a point on the axial line.
Solution hidden
Log in to view solution →
Q44
long answer
What is nuclear reactor ? Write note on Moderators, Control rods and Cooling system.
Solution hidden
Log in to view solution →