Chemistry----Spectroscopy And Its Applications

                               Spectroscopy And Its Applications

2-marks/4-marks

1.      Define electromagnetic spectrum.

2.      Define spectroscopy.

3.      Define Wave number.

4.      What is chemical shift.

5.      Explain briefly the various types of molecular transitions.

6.      What is UV spectrum? Give various regions associated with UV spectrum.

7.      State Franck Condon Principle. Also explain its use.

8.      Define (a) Bathochromic Shift (b) Hypsochromic Shift

9.      Explain Isobestic Point.

10.  State major applications of UV Spectroscopy.

11.  What are molecular Vibrations? State its types.

12.  State the major applications of Infrared Spectroscopy.

13.  Why TMS is used as a reference standard in NMR Spectroscopy?

14.  Explain Spin-Spin Coupling.

15.  How many NMR signals will be given by each of following compounds?

      (a) Ethyl Acetate         (b) Acetone     (c) Diethyl ether

16. Define Allowed and Forbidden Transitions.

17. State Lambert-Beer Law.

18. What is fingerprint region in IR?

19. State the factors affecting chemical Shift?

20. Explain Spin-Spin Coupling in detail.

       6-marks/8-marks

   1. (a) State and explain the principle of NMR Spectroscopy.

    (b) State the working of NMR Spectrometer.

2. (a)  Explain  (i) Intensities of spectral line (ii) Width of spectral line

     (b) State Frank Codon Principle.

3. Discuss IR spectroscopy and state its various applications.

4. (a) Explain the working of UV spectrometer.

    (b) Define (i) Auxochromes      (ii) Chromophores

5.  Explain following terms:

      (a) Blue Shift             

      (b) Red Shift

      (c) Hyperchromic effect

      (d) Isobestic Point                  

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PTU Important Questions----Fibre Optics

       Physics:

Important Questions related to chapter --Fiber Optics.

 2-marks/4-marks

Q1. Define Numerical aperture, Acceptance angle.
Q2. Define Total Internal reflection of light
Q3. State the basic principle behind fibre optics.
Q4. What do you mean by attenuation in optical fibres?
Q5. Define Normalized frequency / Define V-Number. Deduce an expression for
      V-Number.
Q6. Differentiate b/w single mode and multi mode optical fibre.
Q7. What do you mean by mode in an optical fibre?
Q8. Distinguish b/w step index and graded index optical fibre.
Q9. What are the qualities of a fibre optic material?
Q10. What is an optic fibre sensor?
Q11. derive the relation b/w Numerical aperture and Fractional Refractive Index.
Q12. State the advantages of fibre optic communication over copper cable
         communication.
Q13. Describe (i) Splicer (ii) Coupler (iii) Connector
Q14. What do you understand  by  Single  mode  and  Multimode fibre?
Q15. State major advantages of fibre communication.
Q16. Give  important applications of  optical  fibres.

6-marks/8-marks


Q1. (a)  Describe  construction  of an  optical  fiber  with help  of diagram.  Further,
             describe  different  factors  responsible  for  loss  of  signal  propagating
             through  a  fiber.
      (b)  Calculate  the  numerical  aperture,  acceptance  angle  and
            the critical  angle of a  fiber  having  core  and  cladding  refractive  indices
            as  1.5  and  1.45,
            respective.

Q2. (a) Derive the expression for numerical aperture, acceptance angle and angle of
             acceptance cone.
       (b) An optical fibre has core refractive index 1.5 and cladding refractive index
            1.47. Calculate critical angle at core cladding intrface.

Q3. (a) State and explain various losses that occur in fibre transmission.
       (b) State various applications of optical fibres in different fields.

Q4. (a) What are Step index and Graded index optical fibres? Explain the
            propagation of signals in step index and graded index optical fibres.
       (b) Calculate (i) Numerical aperture (ii) Acceptance angle of a fibre having core
             refractive index 1.6 and cladding refractive index 1.58.

Q5. (a)  Find  the  core radius  necessary  for  single mode  operation  at  820  nm
             of  a step  index  fibre  with  n1:  1.480  and n2:  1.478.
       (b)  Differentiate  between  material  dispersion  and  pulse  dispersion.  Write
             down  various  types  of losses  in optical fibre.

Q6. (a)  Explain  the  difference  between  a  step-index  fibre  and  graded
              index  fibre.
       (b)  What  is  meant  by  acceptance  angle  for  an  optical  fibre?  Show
              how  it  is related  to  numerical  aperture.

Q7. (a) A 20 km long fibre cable has a loss of 2 dB/Km and connector loss of
            0.6 dB/Km. Find the total loss.
       (b) Derive an expression for pulse broadening due to intermodal dispersion in
             multimode step index optical fibre.

Q8.  a) The core  of a glass  fibre has  a refractive  index  of 1.6 while its cladding is
            doped  to give a fractional change  in refractive  index  of 0.008.  Find
            refractive index of cladding and the critical  internal  reflecting angle.
       b)  Elaborate important  characteristics  of step index fibres.

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PTU Important Questions----LASERS

                                   Physics:



Important Questions related to chapter --LASERS.


 2-marks/4-marks


Q1. What is laser?
Q2. What is holography?
Q3. Explain how a laser light is different from ordinary light?
Q4. Explain the terms:
      1)Stimulated emission 2) Population Inversion 3) Optical Pumping
      4)Stimulated absorption
Q5. State any four methods of pumping a laser.
Q6. Explain how a hologram differs from phtograph?
Q7. Explain spiking process.
Q8. Differentiate between spatial coherence and temporal coherence.
Q9. Differentiate between 3-level and 4-level laser.
Q10. Are all holograms same?
Q11.write physical significance of Einstein's coefficients.
Q12. Explain the role of Helium in He-Ne laser.
Q13. Differentiate between spontaneous emission and stimulated emission.
Q14.State any two applications of Holography.
Q15. Explain why a 4-level laser is preferred over 3-level laser although it has low efficiency?
Q16. What do you mean by coherance length? write down the expression for it.
Q17. What is the wavelength of He-Ne Laser, Semiconductor Laser?

6-marks/8-marks

Q1. a) Explain the construction, working and the energy level diagram for
           He-Ne laser.
       b) Explain process of spiking in Ruby laser.

Q2. a) Explain the construction, working and the energy level diagram for Ruby laser.
       b) Define Einstein coefficients and give their significance.

Q3. What do you understand by holography? Derive the relationship between
       Einstein coefficients.

image source: lasers.llnl.gov

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Magnetic Materials & Superconductivity

Physics:

Important Questions related to chapter --Magnetic Materials and Superconductivity



2-marks/4-marks

Q1. Derive the relation b/w Permeability and Susceptibility.
Q2.State and explain the chief origin of magnetic moment for electrons.
Q3. State any four characteristics of ferromagnetic materials.
Q4. Define 1) Curie Temperature 2) Neel Temperature .
Q5. Define 1) Remanence 2) Coericivity .
Q6. What are ferrites? State few properties of ferrites. Give their useful applications.
Q7. What is magnetostriction?
Q8. What is magnetic anisotropy?
Q9. Differentiate b/w Soft and Hard magnetic materials.
Q10. Define 1) Magnetic flux density 2) Intensity of magnetisation .
Q11. Why ferromagnetism is lost on heating?
Q12. What is Meissners effect?

Q13. What do you mean by Cooper pairs?
Q14. Compare Type-I and Type-II superconductors.
Q15. Define critical magnetic field and critical temperature of a superconductor.
Q16. What is Superconductivity? Define persistent current.
Q17.  What is the difference b/w perfect Diamagnet and  Superconductor?


6-Marks/8-marks

Q1. State and explain Domain Theory of ferromagnetism.

OR

      Discuss domain structure in ferromagnetic materials.
Q2. i)Explain BCS theory of superconductivity.
      ii) Explain Meissner Effect.
Q3. What are London Equations? Explain the expression for the penetration depth of
       Superconductors.




Important questions related to chapter LASERS .
image source: personal.psu.edu

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Basic Knowledge

In next few posts, I will be posting stuff related to Ist year students, starting off with physics group.
So, let the game begin.

For those who have just entered in physics Ist year and wondering what physics group or chemistry groups mean, let me tell you that in Ist year you will be learning under the tag of Applied Sciences.

Applied Science is further divided in two halves:

1)Physics group                                                     2)Chemistry Group

Physics group consists of following subjects:

• Engg. Physics
• B.E.E.E. (Basic Electrical And Electronics Engg.)
• C.E. (Communicative English)
• Engg. Maths-1  
• H.V.P.E. (Human Values And Professional Ethics)
• Workshop or Manufacturing Practice (No written Paper)

Chemistry group consists of following subjects:

• Engg. Chemistry
• Environmental Science
• Elements of Mechanical Engg.
• Engg. Maths-2
• F.C.P.I.T. (Fundamentals Of Comp. Programming And IT )
• E.D. (Engg. Drawing)

So, In Ist year Subjects are common for all streams.




Get started with Physics and read some Important questions related to chapter EM waves and Dielectrics.

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Introduction

Study material related to PTU--(Punjab Technical University) is available in very small quantity and with zero quality.

So, aim of this blog is to provide quality stuff to easily pass PTU exams.
On this blog, several important Q and A, previous years papers and other study material will be provided free of cost.

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