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AU COE QP 1 27663T Reg. No. Question Paper Code : 27663T B.E./B.Tech. DEGREE EXAMINATION, DECEMBER 2015/JANUARY 2016 First Semester Civil Engineering PH 6151 T – ENGINEERING PHYSICS – I (Common to all Branches) (Regulations - 2013) Time : Three Hours Maximum : 100 Marks Planck’s constant = 6.62 × 10 –34 Js ©[ô]d Uô±- = 6.62 × 10 –34 Js Speed of light = 3 × 10 8 ms –1 J°«u úYLm = 3 × 10 8 ms –1 Electron rest mass = 9.11 × 10 –31 kg GXdhWôu ¨ûX¨û\ = 9.11 × 10 –31 kg Proton rest mass = 1.67 × 10 –27 kg ×úWôhPôu ¨ûX¨û\ = 1.67 × 10 –27 kg Answer ALL questions. Aû]jÕ ®]ôdLÞdÏm ®ûPV° PART – A (10 × 2 = 20 Marks) Tϧ þ A (10 × 2 = 20 U§lùTiLs) 1. Draw the Bravais lattices belonging to the orthorhombic crystal system. ÏjÕ NônNÕWØ¡«u ©WûYv Rh¥L°u TPeLû[ YûWL.
Transcript

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1 27663T

Reg. No.

Question Paper Code : 27663T

B.E./B.Tech. DEGREE EXAMINATION, DECEMBER 2015/JANUARY 2016

First Semester

Civil Engineering

PH 6151 T – ENGINEERING PHYSICS – I

(Common to all Branches)

(Regulations - 2013)

Time : Three Hours Maximum : 100 Marks Planck’s constant = 6.62 × 10–34 Js

©[ô]d Uô±− = 6.62 × 10–34 Js

Speed of light = 3 × 108 ms–1

J°«u úYLm = 3 × 108 ms–1

Electron rest mass = 9.11 × 10–31 kg

GXdhWôu ¨ûX¨û\ = 9.11 × 10–31 kg

Proton rest mass = 1.67 × 10–27 kg

×úWôhPôu ¨ûX¨û\ = 1.67 × 10–27 kg

Answer ALL questions.

Aû]jÕ ®]ôdLÞdÏm ®ûPV°

PART – A (10 ×××× 2 = 20 Marks)

Tϧ þ A (10 ×××× 2 = 20 U§lùTiLs)

1. Draw the Bravais lattices belonging to the orthorhombic crystal system.

ÏjÕ NônNÕWØ¡«u ©WûYv Rh¥L°u TPeLû[ YûWL.

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2. Calculate the volume of an FCC unit cell in terms of the atomic radius R.

JÚ ØLûUV L]NÕWØûPV AXÏdLX²u TÚUû]

AÔ®u BWjûRd (R) ùLôiÓ LQd¡ÓL.

3. When a wire is bent back and forth, it becomes hot. Why ?

JÚ Lm©ûV Øuàm ©uàm Yû[dÏmúTôÕ ãPô¡\Õ. Hu ?

4. A metal cube takes 5 minutes to cool from 60 °C to 52 °C. How much time will it take to cool to 44 °C, if the temperature of the surroundings is 32 °C ?

JÚ L]f NÕW EúXôLm 60 °C -−ÚkÕ 52 °C - BL Ï°oYRtdÏ 5

¨ªPm B¡\Õ. ãZ−u ùYlT¨ûX 32 °C - BL CÚl©u

AlùTôÚ°u ùYlT¨ûX 44 °C - BL Ïû\YRtÏ GqY[Ü LôXm GÓjÕdùLôsÞm ?

5. The room temperature (27 °C) thermal neutrons are used in the neutron diffraction experiments. Calculate the de Broglie wavelength associated with these neutrons. The

rest mass of the neutron, mn, is 1.6748 × 10–27 kg.

Aû\ ùYlT¨ûX«Ûs[ (27 °C) ¨ëhWôuLs ®°m× ®û[Ü úNôRû]dÏ TVuTÓjRlTÓ¡u\]. CkR ùYlT ¨ëhWôu L°u ¥ ©Wôd− AûX¿[jûR LQd¡ÓL. ¨ëhWô²u KnÜ

¨û\Vô]Õ 1.6748 × 10–27 ¡¡.

6. Why should the wavefunction of a particle be normalized ?

JÚ ÕL°u AûXfNôo× CVpTôdLlTÓYÕ Hu ?

7. A single mosquito create a sound level of 0 dB. What will be total sound intensity level of 200 such mosquitoes ?

JÚ ùLôÑ®]ôp EiPôÏm J−fùN±Ü UhPm 0 ùP£ùTp G²p, 200 ùLôÑdL[ôp EiPôÏm ùRôÏl× J−«u ùN±Ü UhPm VôÕ ?

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8. In magnetosriction method, calculate the fundamental frequency of ultrasonic waves to be produced by 3.6 cm length of a copper rod fixed at its centre. The speed of sound in this rod is 3600 m/s.

JÚ Tt±l ùTôÚj§Vôp 3.6 ùN. Á ¿[Øs[ RôªWdLm©«u SÓ®p CßLl ùTôÚjRlThÓ, LôkR ÏßdL Øû\«p úRôtß®dLlTÓm ÁùVô−«u A¥lTûP A§oùYiûQd LôiL. CkRd Lm©«p J−«u úYLm 3600 Á/ùN BÏm.

9. For a laser at 2.0 m distance from the laser output beam spot diameter is 6.0 mm and beam divergence is 1.2 m rad. Calculate the beam spot diameter at 5.0 m distance from the laser output.

JÚ úXNo J° ×\lTÓªPj§−ÚkÕ 2 Á ùRôûX®p ARu ®hPm 6 ª. Á G]Üm, J°dLtû\«u ®¬Ü 1.2 ªp− úW¥Vm G²p, 5 Á ùRôûX®p ARu ®hPjûR LQd¡ÓL.

10. Why is intermodal dispersion reduced in graded-index fibers ?

JÚ T¥¨ûX ϱùVi Tp Y¯¨ûX CûZ«p CûP þ Y¯¨ûXL°p ©¬ûL«u A[Ü Ïû\dLlTÓYÕ Hu ?

PART – B (5 ×××× 16 = 80 Marks)

Tϧþ B (5 ×××× 16 = 80 U§lùTiLs)

11. (a) (i) Discuss in detail a suitable method to grow single crystal of semiconducting materials. (12)

Ïû\dLPj§ ùTôÚhL°u Jtû\ T¥LeLs Y[W JÚ

ùTôÚjRUô] Øû\ûVlTt± ®¬YôL ®Yô§dL. (12)

(ii) Metallic iron changes from BCC to FCC at 910 °C and corresponding atomic radii vary from 1.258 Å to 1.292 Å. Calculate the percentage volume change during this structural change. (4)

910 °C Cp EúXôL CÚm× BCC CÚkÕ FCC dÏ

Uôß¡\Õ. AÔ BWeLs 1.258 Å CÚkÕ 1.292 Å Uôß¡u\]. AlúTôÕ ¨LÝm TÚUu Uôt\jûR

LQd¡ÓL. (4)

OR / ApXÕ

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(b) (i) Calculate the packing fraction of FCC and HCP. (12)

FCC Utßm HCP CYt±u AÓdÏRp LôW¦ûV

YÚ®jÕ LQd¡ÓL. (12)

(ii) A hypothetical compound AB is crystallized in simple cubic structure. In this structure the atom A is at the corners and the atom B is at the centre of the unit cell. If the diameter of the atom A is double that of atom B, calculate the packing factor. (4)

AB Gu\ JÚ AÖUô²dLlThP LXûY JÚ G°V L]NÕW LhPûUl©p Es[Õ. AXÏdLX²u

êûXL°p A AÔÜm ûUVj§p B AÔÜm Es[Õ. A

AÔ®u ®hPm B- ûV ®P CÚUPeLôL

CÚdÏmúTôÕ AÓdÏRp LôW¦ûV LQd¡ÓL. (4)

12. (a) (i) Derive the expression for the Young's modulus of a cantilever beam and explain the experiment to determine the Young's modulus of a cantilever beam. (12)

Yû[fNPj§u êXm JÚ Ri¥u Ve ÏQLjûR LôiTRtLôQ úLôûYûV YÚ®dLÜm. ARu Ve ÏQLjûR LôiTRtLôQ úNôRû]ûVÙm ®[dLUôL

®Y¬dLÜm. (12)

(ii) A uniform rectangular bar of 1.0 m long, 2.5 cm breadth and 4.9 mm thickness is supported on its flat face symmetrically on two knife edges 80 cm apart. If loads of 0.125 kg are hung from the two ends, calculate the radius of the curvature of the bar in equilibrium position. Young's modulus

of the materials is 12 × l09 N/m2. (4)

1.0 Á ¿[m, 2.5 ùNÁ ALXm Utßm 4.9 ªÁ R¥Uu ùLôiP JÚ ºWô] ùNqYL NhPm Juß NUfºWôL 80 ùNÁ CûPùY°«p CWiÓ Lj§ ®°m×Ls ÁÕ ûYdLlTÓ¡\Õ. 0.125 ¡¡ GûP CÚ Øû]L°Ûm CÚkÕ ùRôeL®PlTÓ¡\Õ Gu\ôp NU¨ûX ¨ûX«p ThûP Yû[®u BWm LQd¡ÓL. ùNqYL

NhPj§u Ve ÏQLm 12 × l09 ¨/Á2 (4)

OR / ApXÕ

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(b) (i) Describe the theory of radial flow of heat and explain the experiment of determining coefficient of thermal conductivity of a thick rubber pipe through which steam is flowing. (12)

BWdLôp TônÜ Øû\«p ùYlTm LPjÕm §\àdLô] úLôhTôhûP ®Y¬dLÜm AjÕPu R¥U]ô] WlTo ÏZôndÏs TôÙm ¿Wô®«u êXm WlT¬u ùYlTdLPjÕm GiûQd LiÓ©¥dL ERÜm úNôRû]ûV ®[dÏL. (12)

(ii) Write down the formula for the coefficient of thermal conductivity of square shaped thin bad conductor in the Lees' disc method. In this experiment instead of metallic disc, metallic square plate is used. (4)

Äv YhÓ Øû\«p NÕW Y¥YØûPV ùUp−V R¥Uu ùLôiP A¬§t LPj§«u ùYlTd LPjÕ GiÔdLô] ãj§WjûR GÝÕL. CkR úNôRû]«p YhP Y¥Y EúXôLjRhÓdÏ T§XôL NÕW Y¥YØûPV EúXôLjRhÓ TVuTÓjRlTÓ¡\Õ. (4)

13. (a) (i) Derive Planck's law for black body radiation. (12)

LÚmùTôÚs L§oÅfÑdLô] ©[ôe¡u ®§ûV úLôûYVôL YÚ®dLÜm. (12)

(ii) The wavelength of the scattered X-ray photons are determined to be 1.000 Å by the detector at an angle θ° in a Compton experiment. If the wavelength of the scattered photons are found to be 1.018 Å by rotating the detector increasingly through 60° further, then calculate the angles of the scattered X-ray photons. (4)

JÚ LômlPu úNôRû]«p £RßiP úTôhPôuL°u AûX¿[eLû[ LQd¡Óm úTôÕ,

ØR−p θ° Gu\ úLôQj§u Y¯VôL YÚm úTôhPôuL°u AûX¿[Uô]Õ 1.000 Å - BL EQoYô] êXm LiP±VlTÓ¡\Õ. EQoYôû]

úUÛm 60° A§L¬jÕ ÑZtßm úTôÕ AkRd úLôQj§u Y¯VôL YÚm úTôhPôuL°u AûX¿[Uô]Õ 1.018 Å BL LiP±Vl TÓUô]ôp £RßiP úTôhPôuL°u úLôQeLû[ LQd¡ÓL. (4)

OR / ApXÕ

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(b) Derive the time dependent Schrodinger wave equation from that obtain time-independent wave equation. (16)

xúWô¥eL¬u úSWm NôokR AûXfNUuTôhûP RÚ®jÕ ARu êXm úSWm Nôok§WôR AûXfNUuTôhûP

YÚ®dLÜm. (16)

14. (a) Obtain Sabine's expression for reverberation in a hall. (16)

G§o ØZdL LôXj§tLô] NûTu YônTôhûP

YÚ®dLÜm. (16)

OR / ApXÕ

(b) (i) Explain with neat diagram, principle, construction, working of piezoelectric method to produce ultrasonics. (12)

AÝjR þ ªu AûX«Vt±«u úLôhTôÓ, LhPûUl×, ùNVpØû\ûV RÏkR TPjÕPu ®Y¬dLÜm. ARu

¨û\ Ïû\Lû[d áßL. (12)

(ii) Two ships A and B are anchored at some distance away in the deep sea. An ultrasonic signal of 50 kHz is sent simultaneously from one ship to another by two routes through sea-water and through air. The speeds of sound in sea-water and in air are 1372 m/s and 343 m/s. If the signals are received in the ship with the time gap of 3 s, then calculate distance between the two ships. (4)

BZUô] LP−p CÚ LlTpLs ùLôgNm çWm CûPùY°«p SeáWm Tônf£ ¨t¡u\]. JÚ

LlT−p CÚkÕ Utù\ôß LlTÛdÏ 50 kHz

A§oùYiÔûPV ÁùVô− ûNûLL[ô]Õ CÚ Y¯L°p, Juß LPp ¿o Y¯VôLÜm Utù\ôuß Lôtß Y¯VôLÜm JúW úSWj§p AàlTlTÓ¡u\]. Utù\ôß LlTÛdÏ YkRûPkR ûNûLLÞd¡ûPúV úSW CûPùY° 3 ùSô¥ G²p, CÚ LlTpLÞdÏ ªûPúV Es[ ùRôûXûY LQd¡ÓL. LPp ¿¬Ûm Lôt±Ûm J−«u úYLm Øû\úV 1372 Á/ùN, 343

Á/ùN BÏm. (4)

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15. (a) Describe the construction and working of CO2 laser with neat diagram and write

down its applications. (16)

CO2 úXN¬u AûUl× ùNVpTôÓ Tt± RÏkR TPeLÞPu

®Y¬ Utßm AYt±u TViTôÓLû[Ùm GÝÕL. (16)

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(b) (i) Obtain the expression for numerical aperture of an optical fiber. (12)

JÚ J° CûZ«u GiQ[Ü ÖûZÜjÕû[dLô]

úLôûYûV YÚ®dLÜm. (12)

(ii) For a heterojunction semiconductor laser, the band gap of the semiconductor used is 1.44 eV. By doping, the band gap of the semiconductor is increased by 0.2 eV. Calculate the change in the wavelength of the laser. (4)

JÚ úY±u Nk§ Ïû\LPj§ úXN¬p TVuTÓjRlTÓm

Ïû\LPj§«u Bt\p CûPùY° 1.44 eV BL CÚd¡\Õ. UôÑd LXl©]ôp Ïû\ LPj§«u Bt\p

CûPùY° úUÛm 0.2 eV A§L¬jÕs[Õ. úXNo

AûX¿[m Uôt\m LQd¡ÓL. (4)

______________

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Reg. No. :

B.E./B.Tech. DEGREE EXAMINATION, JANUARY 2014.

First Semester

Civil Engineering

PH 6151 T — ENGINEERING PHYSICS — I

(Common to all branches)

(Regulation 2013)

Time : Three hours Maximum : 100 marks

Answer ALL questions.

PART A — (10 × 2 = 20 marks)

1. ‰» A»S ö\À (primitive cell) GßÓõÀ GßÚ? G.Põ. u¸P. What is a primitive cell? Give an example. 2. E¸Q¯ {ø»°À C¸¢x £iP® ÁͺUS® H÷uÝ® ]» •øÓPÎß ö£¯ºPøÍ

SÔ¨¤kP.

Name few techniques of crystal growth from melt. 3. 3m }Í® ©ØÖ® 1mm Âmh® öPõsh uõªµ P®¤¯õÚx 5N öPõsh CÊ Âø\US

Em£kzu¨£mhõÀ E¸ÁõS® }Í AvP›¨ø£ Psk¤i. öPõkUP¨£mhøÁ uõªµzvß £[SnP® = 120 GPa.

A copper wire of 3m length and 1mm diameter is subjected to a tension of 5N. Calculate the elongation produced in the wire if the Young’s modulas of copper is 120 GPa.

4. {³mhß S뼀 Âvø¯ TÖP.

State Newton’s law of cooling. 5. 1Å }Í® öPõsh J¸ £›©õn ö£mi°À AøhUP¨£mi¸US® Gö»UmµõÛß

uõÌÄ ©mh BØÓø» Psk¤i.

öPõkUP¨£mhøÁ

Gö»UmµõÛß {øÓ kg101.9 31−×=

¤Íõ[U ©õÔ¼ JS106.625 34−×=

Find the lowest energy of electron confined to move in a one dimensional box of length 1Å. Given.

JS.106.625

kg101.934

31

×=

×=

λe

m

Question Paper Code : 37006 T

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37006 T 2

6. FkÖÄ Gö»Umµõß ~s÷nõUQ°ß uzxÁzøu GÊxP.

Write the principle of transmission electron microscope.

7. «ö¯õ¼ Aø»PÒ ªßPõ¢u Aø»PÍõ? ÂÍUSP.

State Weber-Fechner law.

8. Cµsk Pmh Aø©¨¤øÚ £¯ß£kzv ÷»\øµ ÷uõØÖÂUP •i²©õ? ÂÍUSP.

Are ultrasonic waves electromagnetic waves in nature? Explain.

9. \õuõµn uPÁÀ öuõhºø£ Põmi¾® JÎ CøÇ öuõhº¤ß H÷uÝ® |õßS ]Ó¨¤¯À¦PøÍ GÊxP.

Can a two level system be used for the production of laser? Why?

10. Kΰ¯À CøÇ öuõhº¦ \õuÚ[PÐUS® ©ØÓ öuõhº¦ \õuÚ[PÐUS® Cøh÷¯¯õÚ H÷uÝ® |õßS ÷ÁÖ£õkPøÍU TÖP.

Write any four major advantages of optical fibre communication over other communication systems.

PART B — (5 × 16 = 80 marks)

11. (a) (i) ö£õvÄ ¤ßÚÀ GßÓõÀ GßÚ? AÖ[÷Põn ö|¸UP ö£õvÄ Aø©¨¤ß ö£õvÄ ¤ßÚ® 0.74 GÚUPõmkP. (2 + 10)

(ii) uõªµ©õÚx •Pø©¯ PÚ\xµ C¯»ø©¨¦ (FCC) öPõskÒÍx. Auß Aq Bµ® 1.273Å GÛÀ

(1) AoU÷PõøÁ Põµo ©ØÖ® (2)

(2) uõªµzvß Ahºzvø¯ Psk¤i. (2)

öPõkUP¨£mhøÁ

uõªµzvß Aq Gøh = 63.5

AÁPõm÷µõ Gs = 6.026×1026 mol–1.

(i) What is packing factor? Prove that the packing factor of HCP is 0.74. (2 + 10)

(ii) Copper has FCC structure and its atomic radius is 1.273Å. Find

(1) Lattice parameter and (2)

(2) Density of copper. (2)

Given

Atomic weight of copper = 63.5

Avagadro’s number = 6.026×1026 mol–1.

Or

(b) (i) ¤›m÷©ß (Bridgmann) •øÓ°À £iP® ÁͺUS® •øÓ°øÚ ÂÍUSP. (8)

(ii) ÷Áv B £iÄ (CVD) •øÓ°øÚ ÂÁ›UP. (8)

(i) Describe Bridgmann method of crystal growth. (8)

(ii) Briefly explain the Chemical Vapour Deposition (CVD) method. (8)

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12. (a) (i) J¸ ÁøÍÄ \mhzvß £Ð öuõ[P¨£k® ÷£õx E¸ÁõS® ÁøÍÄU ÷PõøÁø¯ (depression) u¸Â. (12)

(ii) I&ÁiÁ Q›hºPøÍ £ØÔ GÊxP. (4)

(i) Derive an expression for depression at the free end of cantilever due to load. (12)

(ii) Give an account of I-shape Girders. (4)

Or

(b) ½ Ámk •øÓ°À J¸ A›vØ Phzv°ß öÁ¨£[PhzxvÓøÚ Psk¤iUS® •øÓ°øÚ £ØÔ Â›ÁõP ÂÍUSP. (16)

Describe with theory Lee’s disc method of determination of thermal conductivity of a bad conductor. (16)

13. (a) (i) ¤Íõ[U PvºÃa_ ÂvUPõÚ ÷PõøÁø¯ u¸ÂUP. (12)

(ii) Põ®hß ]uÓÀ ÷\õuøÚ°À £kQßÓ ÷£õmhõÛß Aø» }Í® 3Å GÛÀ £kQßÓ ÷£õmhõÛß vø\°À 60° ÷PõnzvÀ £õºUS® ÷£õx ]uÓ»øhzu ÷£õmhõÛß Aø»}Ízøu Psk¤i. (4)

öPõkUP¨£mhøÁ

.ms103C

Js106.625

Kg101.9M

18

34

3e

×=

×=

×=

λ

(i) Derive Planck’s law of radiation. (12)

(ii) In a Compton scattering experiment the incident photons have a wavelength of 3Å. What is the wavelength of the scattered photons if they are viewed at an angle of 60° to the direction of incidence? (4)

Given :

.ms103C

Js106.625

Kg101.9M

18

34

3e

×=

×=

×=

λ

Or

(b) Á›UPs÷nõmh Gö»Umµõß ~s÷nõUQ°ß (SEM) uzxÁ® ö\¯À£k® Âu®, {øÓ£õkPÒ ©ØÖ® SøÓ£õkPøÍ ÂÍUSP. (16)

Write the principle, working, advantages and disadvantages of scanning electron microscope. (16)

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37006 T 4

14. (a) J¸ AøÓ°ß Gvº•ÇUP ÷|µzvØPõÚ \Lø£ß \©ß£õmiøÚ TÔ ÂÍUSP. ÷©¾® Gvº•ÊUP ÷|µzvØPõÚ \Lø£ß \©ß£õmiøÚ u¸Â. (2+14)

State and explain Sabine’s formula for reverberation time of a hall. Derive Sabine’s formula for reverberation time. (16)

Or

(b) (i) ¥÷\õ ªßÂøÍÄ •øÓ°øÚ ÂÍUS. ÷©¾® C®•øÓø¯ £¯ß£kzv «ö¯õ¼ Aø»PøÍ ÷uõØÖ¨£øu ÂÁ›UPÄ®. (2 + 10)

(ii) J¼URØÓo ÷\õuøÚ°À, J¸ vµÁzvß ÁÈ÷¯ ö\À¾® «ö¯õ¼ Aø»PÎß vø\÷ÁPzøu RÌPsh ©v¨¤øÚ øÁzx Psk¤i.

J롧 Aø»}Í® = 600nm

«ö¯õ¼ Aø»PÎß AvºöÁs = 100MHz

Âή¦ ÂøÍÄ÷Põn® = °5

(i) Explain Piezo-electric effect. Describe the piezo-electric method of producing ultrasonic waves. (2 + 10)

(ii) Calculate the velocity of ultrasonic waves in a liquid in an acoustic grating experiment using the following data. (4)

Wavelength of light used = 600nm

Frequency of ultrasonic waves = 100MHz

Angle of diffraction = °5

15. (a) (i) 2Co ÷»\›ß Pmhø©¨¦ ©ØÖ® ö\¯À£k® Âuzøu ÂÍUSP. ÷©¾®

Auß £¯ß£õkPøÍ GÊxP.

(ii) J¸ SøÓUPhzv ÷»\›ß £møh CøhöÁÎ eV9.0 GÛÀ, AvÀ

öÁίõS® J롧 Aø»}Ízøu Psk¤i.

öPõkUP¨£mhøÁ

Js

smC

34

8

10625.6

/103−×=

×=

λ.

(i) Describe the construction and working of 2Co laser and their uses. (14)

(ii) For a semiconductor laser, the bandgap is eV9.0 . What is the wavelength of light emitted from it. (2)

Or

(b) Ch¨ö£¯ºa] ©ØÖ® öÁ¨£ JÎ CøÇ EnºÂPÎß Pmhø©¨¦ ö\¯À£k® Âuzøu ÂÍUSP.

Explain the construction and working of displacement and Temperature fibre optic sensors. (8+8)

—————————

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Reg. No. :

B.E./B.Tech. DEGREE EXAMINATION, APRIL/MAY 2017.

First Semester

Civil Engineering

PH 6151 T — ENGINEERING PHYSICS — I

(Common to Mechanical Engineering)

(Regulations 2013)

Time : Three hours Maximum : 100 marks

Answer ALL questions.

PART A — (10 2 = 20 marks)

1. A»SUP»ß GßÓõÀ GßÚ?

What is a unit cell?

2. J¸ BCC £iPzvß Âή¤ß AÍÄ 0.36 |õ.« Auß AqÂß Bμzøu PõsP.

Lattice constant of a BCC crystal is 0.36 nm. Find its atomic radius.

3. «m]¯À SnP[PÎß ÁøPPÒ ¯õøÁ?

What are the types of Moduli of elasticity?

4. Áøμ¯Ö : öÁ¨£ Phzx vÓß.

Define thermal conduction.

5. Põ®hß ÂøÍøÁ ÁSzxøμ.

State Compton effect.

6. £›©õØÓ Gö»Umμõß ~s÷nõUQ°ß uzxÁ® ¯õx?

What is the basic principle in transmission electron microscope?

7. Gvº•ÇUP Põ»zøu Áøμ¯Ö.

Define reverberation time.

Question Paper Code : 72383 T

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OE

QP

Ws 20

72383 T 2

8. SONAR GßÓõÀ GßÚ?

What is SONAR?

9. Jΰ¯À CøÇ GßÓõÀ GßÚ?

What is an optical fiber?

10. Nd-YAG ÷»\›ß £¯ß£õkPÒ ¯õøÁ?

What are the applications of Nd-YAG laser?

PART B — (5 16 = 80 marks)

11. (a) ªÀ»º SÔö¯sPÒ ¯õøÁ? J¸ PÚ\xμ umi°À, uÍ[PÐUQøh÷¯²ÒÍ

(hkl) öuõø»ÄUPõÚ ÷PõøÁø¯ Á¸ÂUPÄ®.

What are Miller indices? Derive an expression for the interplanar spacing (hkl) planes of a cubic structure.

Or

(b) RÌUPsh Aø©¨¦PøÍ Â›ÁõP ÂÍUPÄ® :

(i) øÁμ®

(ii) Qμõø£mk.

Explain the following structures :

(i) Diamond (10)

(ii) Graphite (6)

12. (a) \© GøhPøÍ J¸ usiß C¸¦Ó•® øÁzx, usiß ø©¯¨ ¦Òΰß

HØÓzvØPõÚ ÷PõøÁø¯ Á¸ÂUPÄ®. Cuß ¯[ Snzvß PshÔ¯ EuÄ®

÷\õuøÚø¯²® ÂÍUP©õP ÂÁ›UPÄ®.

Derive an expression for the elevation at the centre of a beam which is loaded at both ends. Describe an experiment, to determine the Young’s modulus of a beam loaded at both ends in detail.

Or

(b) ½ì Ámk •øÓ°À A›vØ Phzv°ß öÁ¨£[Phzx vÓÝUPõÚ

÷Põm£õmøh²® AuøÚ PshÔ¯ EuÄ® ÷\õuøÚø¯ ÂÁ›UPÄ®.

Describe with relevant theory the method of determining the co-efficient of thermal conductivity of a bad conductor by Lee’s disc method.

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OE

QP

Ws 20

72383 T 3

13. (a) Gö»UmμõßPÎß Aø»¨ £sø£ EÖv¨£kzv¯ G.P. uõ®\Ûß ÷\õuøÚø¯

ÂÍUSP.

Explain G.P. Thomson experiment to prove the wave nature of an electron.

Or

(b) Gö»Umμõß ~s÷nõUQ°ß uzxÁ® GßÚ? Gö»Umμõß ~s÷nõUQ°ß

Pmhø©¨ø£ £h® Áøμ¢x Auß ö\¯À£õmøh ÂÍUSP. Aøu JÎ

~s÷nõUQ²hß J¨¤kP.

What is the principle of an electron microscopy? Draw the construction of an electron microscope and explain its working. Compare it with optical microscope.

14. (a) Aμ[P J¼°¯ø» £õvUS® PõμoPÒ ¯õøÁ? JÆöÁõ¸ Põμoø¯²®

AÁØøÓ \›ö\´²® •øÓø¯²® ÂÍUSP.

What are the factors affect the acoustics of a building? Explain each factor along with its remedy

Or

(b) (i) J¼°¯À RØÓo GßÓõÀ GßÚ? J¼°¯À RØÓoø¯ £¯ß£kzv J¸

}º©zvÀ «ö¯õ¼°ß vø\÷ÁPzøu AÍÂkÁuØPõÚ ÷\õuøÚø¯

ÂÁ›UPÄ®.

(ii) H÷uÝ® |õßS «ö¯õ¼°ß £¯ß£õmøh TÖP.

(i) What is acoustic grating? Describe the method of determining the velocity of ultrasonic waves using acoustic grating (12)

(ii) Mention any four applications of ultrasonic waves. (4)

15. (a) K›Ú ©ØÖ® ÷ÁÔÚ \¢vPÎÀ Ga-As ÷»\›ß ö\¯À£õmøh uS¢u

£h[PÐhß ÂÁ›.

Explain how laser action is achieved in homojunction and heterojunction Ga-As laser with suitable diagrams.

Or

(b) ¤ßÁ¸ÁÚ £ØÔ ]Ö SÔ¨¦ GÊxP.

(i) EÒ÷|õUS P¸Â.

(ii) CøÇ Jΰ¯À & ö£¯ºa] En›.

Write short notes on :

(i) Endoscope (8)

(ii) Fibre optic - displacement sensor. (8)

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QP

wk14

Reg. No. :

B.E./B.Tech. DEGREE EXAMINATION, APRIL/MAY 2015.

First Semester

Civil Engineering

PH 6151 T — ENGINEERING PHYSICS — I

(Common to Mechanical Engineering)

(Regulation 2013)

Time : Three hours Maximum : 100 marks

¤ÍõÚU ©õÔ¼ = 6.62 × 10–34 J s

J롧 ÷ÁP® = 3 × 108 m s–1

G»Umμõß {ø»{øÓ = 9.11 × 10–31 kg

¦÷μõmhõß {ø»{øÓ = 1.67 × 10–27 kg

Answer ALL questions.

PART A — (10 2 = 20 marks)

1. J¸ Gί PÚ\xμ ö\À¼ß ÷»miì ©õÔ¼ 0.41 nm. A¢u uÍ[PÎß (321) d&CøhöÁÎø¯ Psk¤i.

Calculate the d-spacing of (321) planes of a simple cubic cell of lattice constant 0.41 nm.

2. øÁμ A»S ö\À¼ß J¸[Qøn¨¦ Gs GßÚ?

What is the coordination number of diamond unit cell?

3. J¸ ö£õ¸Îß }m]¨£sø£ GÆÁõÖ öÁ¨£{ø» ©õØÓ® £õvUQÓx?

How does change in temperature affect the elastic property of a material?

4. {³mhÛß Sκa] Âvø¯ GÊxP.

State Newton’s law of cooling.

5. £¸¨ö£õ¸Ò Aø»PÎß C¸ £s¦PøÍ GÊxP.

What is Compton effect?

Question Paper Code : 77274 T

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QP

wk14

77274 T 2

6. J¸ J¸£›©õn ö£mi°ß EÒ EÒÍ J¸ xPÎß Aø» \©ß£õk kxek 2

GÛÀ, k

xk

32 GßÓ ÁmhõμzvÀ A¢u xPÒ C¸¢uõÀ Auß {PÌuPÄ GßÚ?

Given that the wavefunction of a particle in a one dimensional box is given by kxek 2 , evaluate the probability of finding the particle in the region

kx

k32

.

7. J¸ ¦ÒΰÀ 1 dB AÍÄ ö\ÔÄ ©mh® öPõsh J¼ø¯ J¸ ‰»® E¸ÁõUSQÓx

GÛÀ A¢u J¼°ß ö\ÔÄ GßÚ? A source of sound produces an intensity level of 1 dB at a given point.

Calculate the intensity of sound.

8. A ì÷Pß E¯º JÎ öÁΨ£õk Gߣx GßÚ? What is the principle of A-scan display in ultrasonics?

9. CO2 ÷»\›ß O® £¯ß£kzu Põμn® GßÚ? What is the purpose of using helium in CO2 laser?

10. ~soøÇ JÎ öuõhº¦ •øÓ°ß Pmh Áøμ£h® ÁøμP. Draw the block diagram of a fibre optical communication system.

PART B — (5 × 16 = 80 marks)

11. (a) (i) J¸ BCC A»S ö\À¼ß Aøh¨¦ ¤ßÚ® (packing fraction) Põn

÷PõøÁø¯ Á¸Â.

(ii) J¸ ö©Àm (melt) C¸¢x £iPzøu ÁͺUS® ¤›ä÷©ß ~qUPzøu

ÂÍUSP. (i) Derive an expression for packing fraction of a BCC unit cell. (8) (ii) Explain the Bridgman technique of growing crystal from melt. (8)

Or (b) (i) J¸ Gί PÚ\xμ £iPzvÀ (lattice) d&CøhöÁÎ (hkl) uÍ[PÐUPõÚ

÷PõøÁø¯ Á¸Â. (ii) J¸ AÖ÷Põn Aøh¨¦ Pmhø©¨¤À Auß Aøh¨¦ ¤ßÚzøu

(packing fraction) Põq® ÷PõøÁø¯ Á¸Â. (i) Obtain an expression for d-spacing of (hkl) planes of a simple cubic

lattice. (6) (ii) Derive an expression for packing fraction of a hexagonally close

packed structure. (10)

12. (a) (i) J¸ J¸•øÚ uõ[QÂmh® £kUøP¯õP øÁUP¨£mk Auß J¸ •øÚ

CÖUQ¨ ¤izx® ©Ö•øÚ £ÐÄ® ö\¯À£kQÓx. Auß «x £Ð

ö\¯À£k®© ¦Òΰ¾®, ©Ö•øÚ°¾® »UP[PøÍU PõsP. (ii) I ÁiÁ y»[PøÍ ÂÁ›.

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QP

wk14

77274 T 3

(i) A cantilever is clamped horizontally at one end and loaded at the other. Obtain the relation between the depression at the loaded end and the load applied. (12)

(ii) Explain I-shaped girders. (4)

Or

(b) (i) öÁ¨£ Bμ Kmhzøu ÂÁ›. Kμ»S ÷|μzvÀ JÆöÁõ¸ SÖUS

öÁmi¾® Phzu¨£k® öÁ¨£zvØPõÚ ÷PõøÁø¯ Á¸Â.

(ii) öÁ¨£UPhzxvÓß 385 Wm–1k–1 ©ØÖ® 296 Wm–1k–1 öPõsh 50 cm ©ØÖ® 70 cm }Í•ÒÍ A, B GßÓ C¸ \mh[PÒ EÒÍÚ. AøÁPÒ

öÁÀi[ ‰»® CønUP¨£kQÓx. A°ß öÁΕøÚ 363 K, B°ß

öÁΕøÚ 303 K öÁ¨£{ø» EÒÍx. AøÁPÎß SÖUSöÁmk ^μõP

EÒÍöuÚ öPõsk, AøÁPÎß öÁÀi[ ö\´¯¨£mh Cøn¨¤ß

öÁ¨£{ø»ø¯U Psk¤i.

(i) Discuss the radial flow of heat and hence derive an expression for the quantity of heat conducted through any section in unit time. Describe the experiment to determine the thermal conductivity of Rubber. (12)

(ii) Two metal bars A and B are of 50 cm and 70 cm long respectively and have thermal conductivities 385 Wm–1k–1 and 296 Wm–1k–1 respectively. They are joined together by welding. The outer end of A is at 363 K and the cuter end of B is at 303 K. Calculate the temperature at the welded joint assuming that their cross sections are equal. (4)

13. (a) (i) |P¸® xPÎß i ¤μõU Aø»}ÍzøuU PnUQh EuÄ® ÷PõøÁø¯

Á¸Â. £¸¨ö£õ¸Ò Aø»PÒ EÒÍöuÚ {¹¤US® G.P uõ®\ß

u[Pa_¸Ò ÷\õuøøø¯ ÂÁ›.

(ii) J¸ G»UmμõÛß {ø»¯õØÓ¾US \©©õP C¯UP BØÓÀ öPõsh

¦÷μõmhõÛß i ¤μõU¼ Aø»}Ízøu PnUQkP.

(i) What are matter waves? Describe the properties of matter waves. Explain in detail G.P. Thomson’s gold foil experiment that proved the existence of matter waves. (6 + 6)

(ii) Calculate the de-Broglie wavelength of a proton and an electron, accelerated by a potential of 150 V. (4)

Or (b) (i) JØøÓ¨ £›©õn ö£mi°À EÒÍ J¸ xPÎß BØÓø»U PnUQh

EuÄ® ÷PõøÁø¯ Á¸Â. ÷©¾® C¯À¦{ø» Aø» \©ß£õmkUPõÚ

÷PõøÁø¯ Á¸Â. (ii) AP»® 1 ª.« öPõsh J¸ £›©õn ö£mi°ß J¸ •øÚ°¼¸¢x

©Ö•øÚUS ö\ÀÁuØS 1 microgram {øÓ öPõsh J¸ xPÒ 100 s

Gkzx öPõÒQÓx. ö£mi°ß EÒ÷Í {ø»¯õØÓÀ _È GÚÄ®,

öÁÎ÷¯ Gsoh»[Põx GÚÄ® öPõsk, A¢u C¯UPzvß

SÁõsh® Gsøn PnUQkP.

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QP

wk14

77274 T 4

(i) Derive an expression for the energy of a particle in a one dimensional box. Also arrive at an expression for its normalized wavefunction (12)

(ii) A particle of mass one microgram takes 100 s to travel from one end to the other end of an one dimensional box of width 1 mm. Assume that the potential inside and at the walls of the box to be zero and infinity respectively. Determine the quantum number described by this motion. (4)

14. (a) J¸ AøÓ°À J¼°ß \μõ\› BØÓ¼ß Áͺa] Ãu® ©ØÖ® ÷u´Ä

ÃuzvØPõÚ ÷PõøÁø¯ GÊxP. A¢u AøÓ°ß \μõ\› EÔg_ BØÓÀ J¸

ö|õi°À 4

EvA GÚU öPõsk Auß ›Áº£÷μ\ß ÷|μ® (Reverberation time)

Põs£uØPõÚ ÷PõøÁø¯ Á¸Â. E – \μõ\› BØÓÀ Ahºzv, v – J¼°ß

÷ÁP®, A – ö©õzu EÔg_vÓß GÚU öPõÒP. Derive the expressions for rate of growth and rate of decay of average

energy of sound in a hall. Hence derive an expression for reverberation time of the hail assuming that the average energy absorbed by all

surfaces in one second to be equal to 4

EvA where E, v and A represent

average energy density, speed of sound and total absorption by all surfaces respectively. (16)

Or (b) (i) J¸ _ØÖ¨£hzvß ‰»® AÊzuªß AvºÄ©õÛPÎß ‰»® E¯º

J¼PøÍ E¸ÁõUS® uzxÁ®, ÷Áø» ö\´²® •øÓ, u¯õ›¨¦ £ØÔ

GÊxP. (ii) J¼ Aݨ¦uÀ •øÓ ‰»® GÆÁõÖ «ö¯õ¼Pøͨ £¯ß£kzv

Eøh¯õa ÷\õuøÚ ÷©ØöPõÒÁõ´? (i) With a neat circuit diagram, explain the principle, working and

production of ultrasonics by a piezo electric oscillator (12) (ii) Explain briefly the through transmission method of non-

destructively testing a specimen using ultrasonics. (4)

15. (a) ÷uøÁ¯õÚ BØÓÀ©mh £hzxhß Nd-YAG ÷»\›ß Pmk©õÚ®, ÷Áø»

ö\´²® •øÓø¯ ÂÁ›. Nd-YAG ÷»\›ß C¸ £¯ß£õkPÒ ¯õøÁ? Describe with necessary energy level diagram, the construction and

working of Nd-YAG laser. Mention any two applications of Nd-VAG laser. (12 + 4)

Or (b) (i) J¸ JΰøÇ°ß GsxøÍ ©ØÖ® Hئ÷Põn® BQ¯ÁØÖUPõÚ

÷PõøÁø¯ Á¸Â. (ii) ö£õ¸mPÎß ‰»® JΰøÇPøÍ ÁøP¨£kzx® •øÓø¯ ÂÁ›. (i) Derive expressions for numerical aperture and acceptance angle of

an optical fibre. (12) (ii) Discuss the classification of optical fibre based on the materials. (4)

—————————

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QP

wk11

Reg. No. :

B.E./B.Tech. DEGREE EXAMINATION, NOVEMBER/DECEMBER 2016.

First Semester

Civil Engineering

PH 6151 T — ENGINEERING PHYSICS – I

(Common to Mechanical Engineering)

(Regulations 2013)

Time : Three hours Maximum : 100 marks

Answer ALL questions.

PART A — (10 × 2 = 20 marks)

1. AqÂß Bμ® 0.144 nm öPõsh FCC Pmhø©¨¦ öPõsh uÛ©zvß A»S

P»Ûß J¸ £UP }Í® GßÚ?

An element has FCC structure with atomic radius 0.144 nm. Find its lattice

constant.

2. Aq {쨦 Põμo – Áøμ¯Ö.

Define atomic packing factor.

3. Eøh¯UTi¯ ö£õ¸øÍ uPÄ–v›¦ Áøμ£h® ‰»® GÆÁõÖ Aøh¯õÍ®

Põs£õ´?

How will you identify a brittle material from the stress-strain diagram?

4. öÁ¨£Phzx vÓß Áøμ¯Ö.

Define thermal conductivity.

5. J¸ G»Umμõß J¸–£›©õn ö£mi°À JkUP¨£mi¸UQÓx (confined)

A¨ö£miø¯ }Í©õUS® ö£õÊx BØÓÀ {ø» CøhöÁÎ GÆÁõÖ ©õÖ®?

An electron is confined to a one-dimensional box. How does the energy level

spacing changes when the box is made longer?

Question Paper Code : 80839 T

AU C

OE

QP

wk11

80839 T 2

6. Á›UPs÷nõmh ~s÷nõUQ ©ØÖ® Em¦S® G»Umμõß ~s÷nõUQ

Cøh÷¯¯õÚ GuõÁx |õßS ÷ÁÖ£õkPøÍ uμÄ®.

Give any four differences between scanning electron microscope and

transmission electron microscope.

7. J¸ Aμ[Qß _ÁºPÒ 0.10 O.W.U. J¼ EmPÁ¸® SnP® öPõsh ö£õ¸ÍõÀ

ö©õÊP £mi¸UQÓx. A¢u Aμ[QÀ AvP©õÚ Gvº•ÊUPzuõÀ ÷£a_ öuÎÁõP

CÀø». A¢u Aμ[Qß J¼°¯ø» ÷©®£kzu •ßö©õȯ¨£mhx. 0.050 O.W.U.

©ØÖ® 0.150 O.W.U. J¼ EmPÁ¸® SnPzøu öPõsh C¸ ÷ÁÖ ö£õ¸mPÒ

C¸UQÓx. } G¢u ö£õ¸øÍ ÷uº¢öuk¨£õ´? Põμn® TÖ.

An auditorium has a plastered walls with sound absorption co-efficient of

0.10 O.W.U. The speech inside the auditorium is not clear due to too much of

reverberation. It has been proposed to improve the acoustics of the hall. Two

different materials with sound absorption co-efficient of 0.050 O.W.U. and

0.150 O.W.U. are available. Which material you will choose. Give reason.

8. NDT ‰»©õP J¸ ö£õ¸Îß SøÓ£õkPøÍ PshÔ²® ~qUP[PÎß ö£¯º

GÊxP.

Mention the techniques applied to determine the defects within a material

through NDT.

9. öuÔ¨¦ ÂÍUS (flash lamp) ©ØÖ® ÷»\›¼¸¢x öÁΣk® JÎPØøÓPÐUS

EÒÍ ]» ÷ÁÖ£õkPøÍ uμÄ®.

Give some differences between the beam of light from a flash lamp and a laser.

10. J¸ £iÂÈ SÔö¯s JÎ CøÇ EÒÍPzvß JλPÀ Gs 1.5 ©ØÖ®

¦ÓÄøÓ°ß JλPÀ Gs 1.48 BP öPõsi¸UQÓx. EÒÍP–¦ÓÄøÓ

Cøh•PzvÀ, CøÇUPõÚ ©õÖ{ø»U ÷Põnzøu Psk¤i.

A step index optical fibre has a core refractive index of 1.5 and cladding

refractive index of 1.48. Calculate the critical angle at the core-cladding

interface.

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QP

wk11

80839 T 3

PART B — (5 16 = 80 marks)

11. (a) (i) J¸ PÚ\xμ umi°À, uÍ[PÐUQøh÷¯ EÒÍ CøhöÁÎUPõÚ (d)

©ØÖ® AzuÍ[PÎß ªÀ»º SÔö¯sPÐUQøh÷¯ (h k l) EÒÍ

EÓøÁ u¸Â.

(ii) J¸ £iP Aø©¨¦, 0.424 nm umi ©õÔ¼ öPõsh PÚ\xμ Aø©¨¤À

£iP©õQÓx. (110) ©ØÖ® (111) uÍ[PÐUPõÚ CøhöÁÎø¯

PnUQhÄ®. ÷©¾® A¢u uÍ[PøÍ Áøμ¯Ä®.

(i) Deduce the relation between the interplanar distance ‘d’ and the

Miller indices (h k l) of the planes for a cubic system. (10)

(ii) Calculate the interplanar spacing for (110) and (111) planes in a

simple cubic lattice whose lattice constant is 0.424 nm. Also sketch

these planes. (6)

Or

(b) (i) E¸UQ¼¸¢x JØøÓ £iP® ÁͺUS® HuõÁx J¸ •øÓø¯ AÁØÔß

|ßø©PÒ ©ØÖ® Á쮦PÐhß ÂÁ›UPÄ®.

(ii) øÁμ® ©ØÖ® Qμõø£m (graphite) Aø©¨ø£ ÂÁ›.

(i) Describe any one method of growing single crystal from melt along

with the advantages and limitations of the method. (8)

(ii) Describe diamond and graphite structures. (8)

12. (a) (i) J¸ usiß EÒÁøÍÄz v¸¨¦ vÓÝUS›¯ ÷PõøÁø¯ u¸Â.

(ii) C¸ •øÚPξ®, £Ð HØÓ¨£mh, J¸ Gί uõ[Q Âmhzvß

ø©¯¨£Sv°À HØ£k® ÷©À÷|õUQ¨ ö£¯º¢xÒÍ (elevation)

öuõø»ÄUPõÚ ÷PõøÁø¯ u¸Â.

(i) Derive an expression for internal bending moment of a beam. (8)

(ii) Derive an expression for the elevation produced at the centre of a

simply supported beam loaded at both the ends. (8)

Or

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QP

wk11

80839 T 4

(b) (i) ½°ß Ámk •øÓ°À A›vØ Phzv°ß öÁ¨£® Phzx® vÓøÚ

{ºn°US® •øÓø¯ ÂÁ›UPÄ®.

(ii) J¸ _ÁμõÚx J÷μ ui©ß öPõsh ©μ AkUS ©ØÖ® uUøP (cork)

AkUS Põ¨£õßPøÍ öPõsi¸UQÓx. EÒ÷Í EÒÍ öÁ¨£{ø» 20°C

©ØÖ® öÁÎ÷¯ EÒÍ öÁ¨£{ø» 0°C BS®. EÒ÷Í uUøP²®

öÁÎ÷¯ ©μ•® C¸US® ö£õÊx ©μ®–uUøP Cøh•Pzvß

öÁ¨£{ø»ø¯ Psk¤i. ÷©¾® EÒ÷Í ©μ•®, öÁÎ÷¯ uUøP

C¸US® ö£õÊx Cøh•Pzvß öÁ¨£{ø»ø¯ Psk¤i. (©μ® ©ØÖ®

uUøP°ß öÁ¨£® PhzxvÓß 0.13 W/m-K ©ØÖ® 0.046 W/m-K

•øÓ÷¯ BS®).

(i) Describe Lee’s disc method to determine the thermal conductivity of

bad conductors. (12)

(ii) A wall consists of layer of wood and a layer of cork insulation of

same thickness. The temperature inside is 20°C and the

temperature outside is 0°C. Calculate the temperature at the

interface between wood and cork, if the cork is inside and the wood

is outside also find the temperature at the interface if the wood is

inside and the cork is outside. (Thermal conductivity of wood and

cork are 0.13 W/m-K and 0.046 W/m-K respectively). (4)

13. (a) (i) J¸ P¸®ö£õ¸Îß PvºÃa_ {Ó©õø»ø¯ ÂÍUPÄ®, ÷©¾®

¤Íõ[Qß (Planck’s) PvºÃa_ Âvø¯ u¸ÂUPÄ®.

(ii) 0.010 nm Aø»}Í® öPõsh J¸ X-Pvº L÷£õmhõÚõÚx, J¸

G»UmμõÚõÀ 110 ÷PõnzvÀ ]uÖQÓx (Recoiling) G»UmμõÛß

C¯UP BØÓÀ GßÚ?

(i) Explain the radiation spectrum of a black body and derive Planck’s

radiation law. (12)

(ii) An X-ray photon of wavelength 0.010 nm is scattered through

110 by an electron. What is the kinetic energy of the recoiling

electron? (4)

Or

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QP

wk11

80839 T 5

(b) (i) J¸ £›©õn ö£mi°À EÒÍ J¸ xPÐUS Schrodinger Aø»

\©ß£õmøh wºUPÄ®. A¢u xPÒ Ai{ø» ©ØÖ® •uÀ Cμsk E¯º

BØÓÀ {ø»°À C¸US® ö£õÊx Auß Aø» ö\¯À£õk ©ØÖ®

{PÌuPÄ Â{÷¯õPa ö\¯À£õmøh Áøμ¯Ä®.

(ii) 80 kV ªßÚÊzu ÷ÁÖ£õmiÚõÀ •kUP¨£mh G»UmμõÛß i ¤μõU¼

Aø»}Ízøu Psk¤i. A¢u G»UmμõøÚ ÷£õ» A÷u BØÓÀ öPõsh

J¸ X-Pvº L÷£õmhõÛß Aø»}Ízøu Psk¤i.

(i) Solve Schrodinger wave equation for a particle in a one-dimensional

box. Sketch the wave function and probability distribution function

of the particle when it is in the ground state and first two excited

states. (12)

(ii) Find the de Broglie wavelength of an electron accelerated through a

potential difference of 80 kV. Find the wavelength of a X-ray photon

that possess an energy same as that of the electron. (4)

14. (a) J¸ Aμ[PzvÝÒ J¼ BØÓ¼ß Áͺa] Ãu® ©ØÖ® ÃÌa] ÃuzvØPõÚ

÷PõøÁø¯ u¸ÂUPÄ®. ÷©¾® AÁØøÓ Áøμ£h©õP PõmhÄ®.

Gvº–•ÊUPU Põ»zvØPõÚ ÷PõøÁ u¸ÂUPÄ®.

Derive an expression for growth and decay of sound energy inside a hall

and represent them graphically. Find an expression for Reverberation

time. (16)

Or

(b) (i) ªß J¼ Aø»PøÍ E¸ÁõUS® AÊzu–ªß Aø»°¯ØÔß Aø©¨¦

©ØÖ® ö\¯À£õmøh ÂÁ›UPÄ®.

(ii) ÷\õ÷ÚõQμõªß (sonogram) ö\¯À£õmøh _¸UP©õP ÂÍUPÄ®.

(i) Describe the construction and working principle of piezo-electric

oscillator of producing ultrasonic waves. (10)

(ii) Briefly explain the principle of sonogram. (6)

AU C

OE

QP

wk11

80839 T 6

15. (a) IßìøhÛß ysk EªÌÄUPõÚ ÷Põm£õmøh ÂÍUPÄ®. ußÛaø\

EªÌÄ ©ØÖ® ysk EªÌÄUS Cøh÷¯ EÒÍ ÂQuzvØPõÚ ÷PõøÁø¯

u¸ÂUPÄ®.

Explain Einstein’s theory of stimulated emission and derive an

expression for the ratio between spontaneous emission and stimulated

emission. (16)

Or

(b) Jΰ¯À CøÇ°ß ‰»® JÎ £μÄÁuØPõÚ ÷Põm£õmøh ÂÍUPÄ®. Hئ

÷Põn® ©ØÖ® GsnÍÄ ~øÇÄzxøÍUPõÚ ÷PõøÁø¯ u¸ÂUPÄ®.

Explain the principle of propagation of light through an optical fibre and

derive an expression for acceptance angle and numerical aperture. (16)

—————————

AU C

OE

QP

wk 9

Reg. No. :

B.E./B.Tech. DEGREE EXAMINATION, NOVEMBER/DECEMBER 2014.

First Semester

Civil Engineering

PH 6151 T — ENGINEERING PHYSICS — I

(Common to Mechanical Engineering)

(Regulation 2013)

Time : Three hours Maximum : 100 marks

Answer ALL questions.

PART A — (10 2 = 20 marks)

1. £iP ußø©²ÒÍ ö£õ¸Ò ©ØÖ® £iP ußø©¯ØÓ ö£õ¸Ò, CÁØøÓ ÷ÁÖ£kzvU

PõmkP.

Distinguish between crystalline material and amorphous material.

2. miller indices Áøμ¯ÖUP.

Define miller indices.

3. ö£õ¸Îß ö|QÌa] ußø©°øÚ £õvUS® PõμoPøÍU TÖP.

Name the factors which affect the elasticity of a body.

4. öÁ¨£® Phzx® vÓß ©ØÖ® öÁ¨£ £μÁÀ Áøμ¯øÓ ö\´P.

Define thermal conductivity and diffusivity.

5. Wein Ch¨ö£¯ºa] Âvø¯ TÖP.

State the Weins displacement law.

6. \õuõμn ~s÷nõUQø¯ Põmi¾® G»Umμõß ~s÷nõUQ°ÚõÀ EshõS®

£¯ßPøÍU TÖP.

What is the advantage of electron microscope over ordinary microscope?

Question Paper Code : 97139 T

AU C

OE

QP

wk 9

97139 T 2

7. J¸ ö£õ¸Îß J¼ EÔg_uÀ Snzøu Áøμ¯Ö.

Define sound absorption coefficient of a material.

8. «ö¯õ¼ Aø»PÎß |õßS £¯ß£õkPøÍU TÖP.

Mention four applications of ultra sonic waves.

9. uø»RÌ J¼°ß ö£¸UP® GßÓõÀ GßÚ?

What do you mean by population inversion?

10. B¨iPÀ CøÇPÎß £¯ß£õkPÒ TÖP.

What are the uses of optical fibers?

PART B — (5 16 = 80 marks)

11. (a) (i) FCC ©ØÖ® HCP Pmhø©¨¦PÎß packing density \©©õP C¸¨£øu

Põs¤UPÄ®.

(ii) HÊ ÁøP¯õÚ £iUPmhø©¨¦PÒ ©ØÖ® 14 Bravai’s lattices ß

ÁøPPøÍ ÂÁ›.

(i) Show that the packing density of FCC and HCP structures are equal. (8)

(ii) Explain the physical basis of classifying crystals into seven systems and 14 Bravais lattices. (8)

Or

(b) (i) Czochralski’s technique (ii) Bridgman Technique CÁØÔß öPõÒøP,

P¸Â Aø©¨¦ ©ØÖ® ö£õ¸ÒPÒ u¯õ›¨£uØPõÚ ö\¯À£õkPøÍ ÂÁ›.

State the principle and illustrations of (i) Czochralski’s technique (ii) Bridgman Technique for material preparation. (8 + 8)

12. (a) J¸ ÁøÍa\mhzvß {ø»¯õÚ •øÚ°¼¸¢x X öuõø»ÂÀ

öuõ[PÂh¨£mh Gøh¯õÀ HØ£k® öuõ´ÂØPõÚ ÷PõøÁø¯ Á¸ÂUPÄ®.

Derive an expression for the depression of cantilever at a distance X from the fixed end loaded at its free end, neglecting the mass of cantilever. (16)

Or

(b) (i) SøÓPhzv°ß öÁ¨£ PhzxvÓøÚ wº©õo¨£uØPõÚ Lees’ •øÓø¯

ÂÍUSP.

(ii) öuõS¨¦ FhP[PÎß ‰»® ö\À¾® öÁ¨£ KmhzvØPõÚ ÷PõøÁø¯

AøhP.

AU C

OE

QP

wk 9

97139 T 3

(i) Describe Lees’ method for determining the thermal conductivity of glass. (8)

(ii) Derive an expression for the flow of heat through the compound media. (8)

13. (a) Compton effect ©ØÖ® Auß •UQ¯zxÁzøu ÂÍUPÄ®. Aø»}Í® ©õØÓ®,

¤ßÚi¨¦ G»Umμõß ©ØÖ® ¤ßÚi¨¦ ÷Põn® CÁØøÓ öuõhº¦£kzx®

\©ß£õkPøÍ öÁÎU öPõnºP. Põ®¨hß ©õØÓ® GßÓõÀ GßÚ?

Explain Compton effect and its physical significance. Derive the relations giving the change of wavelength, the energy of recoil electron and recoil angle. What is Compton shift? (16)

Or

(b) Shrodinger’s Põ»® \õμõu ©ØÖ® Põ»® \õº¢u \©ß£õkPøÍ ÂÁ›UP.

Derive Shrodinger’s (i) time independent and (ii) time dependent equations for matter waves. (8 + 8)

14. (a) J¸ AøÓ°ß JÍ \®£¢u©õÚ •øÓPøÍ ÂÁ›UPÄ®.

Explain in detail the acoustic demands of a hall. (16)

Or

(b) «ö¯õ¼ Aø»PÒ GßÓõÀ GßÚ? «ö¯õ¼ Aø»PøÍ EØ£zv ö\´²®

magnetostriction •øÓø¯ ÂÍUSP. C¢u •øÓ°ß |ßø©PøÍ TÖP.

What is ultrasonics? Explain the magnetostriction method of producing ultrasonic waves and hence describe its advantages over the piezoelectric method. (2 + 10 + 4)

15. (a) (i) Laser emission GßÓõÀ GßÚ? Cøu AøhÁuØPõÚ •øÓPøÍU TÖP.

(ii) CO2 laser &ß öPõÒøP, P¸Â Aø©¨¦ ©ØÖ® ö\¯À£õkPøÍ

ÂÁ›UP.

(i) Explain what do you mean by laser emission? What are the conditions to achieve it? (2 + 4)

(ii) Give the principle of CO2 laser and explain its working by an energy level diagram. (10)

Or

(b) JÎ CøÇPÒ ÁȯõP JÎ £μÁÀ £ØÔ ÂÁ›US® \©ß£õmiøÚ öÁÎU

öPõnºP. öÁÆ÷ÁÖ ÁøP¯õÚ B¨iPÀ CøÇPøÍ ÂÁ›UP.

Explain the propagation of light through optical fibers and explain the different types of fibers. (8 + 8)

—————————


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