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Shankar Kumar
B.TECH | ELECTRONICS & TELECOMMUNICATION | ESE WRITTEN QUALIFIED | 4 YEARS OF TEACHING Experience..

U
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Thanks you mem for your information and please tell in hindi I am hindi medium student
Thank you sir & All the best for exam
Thank you so much sir 😊😊
  1. Q. Which of the following statement are true regarding Invar FeNi36? 1. It is an alloy of Nickel and iron which contains 36% iron and 64% Nickel. 2. It is an alloy of Nickel and iron which contain 36% of Nickel and 64% iron 3. Invar is used where high dimensional stability is required. 4. Invar struts can be used in pistons to limit their thermal expansion. (a) 1 3 and 4 only (b) 2 3 and 4 only (c) 1 and 4 only (d) 2 and 3 only Invar has a very low coefficient of thermal expansion (1.2 10-6/ C). This is used for products where high dimensional stability is required. FeN36 is consist of 36% Ni and 64%, Fe.


  2. Q. Consider the following statements: 1. In metallic solids, positive lon are surrounded by a sea of delocalised electrons. 2. Metallic solids are conductor of electricity in solid state but not in molten state. 3. Metallic solids are hard but malleable and ductile. Which of the above statement are correct? (a) 1 and 2 only (b) 2 and 3 only (c) 1 and 3 only (d) 12 and 3 Metals are orderly collection of positive ions surrounded by and held together by a sea of free electrons. Metals are conductor of electricity in solid state as well as in molten state. Metals are hard but malleable and ductile. So these can be used for many industrial applications


  3. et Audiente o Au four Branches CE/ ME/ EE! EC


  4. Hello Shankar Kumar O B.Tech- Electronics & Telecommunication Cleared 2017 ESE written& Two times GATE Qualified. 4 Years of teaching experience


  5. Q. Which of the following are true regarding Frankel defect? 1. In Frankel defect small ion is dislocated from its normal site to an interstitial site. 2. In Frenkel defect density of the solid changes. 3. Frenkel defect is shown by ionic substances. Select the correct answer using the codes given below: (a) 1 and 2 only (b) 1 and 3 only (c) 2 and 3 only (d) 1 2 and 3 Frenkel defect is shown by ionic solids. The smaller ion is dislocated from its normal site to an interstitial site. It creates a vacancy defect at its original site and an interstitial defect at its new location. Density of solid remains same in Frenkel defect.


  6. Q. Consider the following statements: 1. Temporary hardness of water is due to the presence of magnesium and calcium chlorides and sulphates. Permanent hardness of water is due to the presence of magnesium and Calcium hydrogen carbonates Boiling and Clark's method are used for removing temporary hardness Calgon's method and lon exchange method are used for removing permanent 2. 3. 4. hardness. Which of the above statement are correct? (a) 1 and 2 only (b) 12 and 3 only (c) 1 2 and 4 only (d) 3 and 4 only Temporary hardness of water is due to presence of magnesium and calcium hydrogen carbonates Permanent hardness is due to the presence of chlorides and sulphates present in water. Boiling and Clark's method is used for removing temporary hardness of water. Permanent hardness of water can be removed using Sodium Carbonate, Calgon's method, Ion-exchange method and synthetic resins method.


  7. Q. What is the structure of martensite? (a) Orthorhombic (b) Body Centred Tetragonal (c) Hexagonal Close Packed (d) Body Centred Cubic Martensite is most brittle and hardest phase of Iron. Martensite has Body Centered Tetragonal structure


  8. Q. Which of the following are incorrect regarding matrix phase? 1. It acts as the medium by which an externally applied stress is transmitted and disturbed to the fibres. 2. It protects the individual fibres from surface damage. 3. The problem with matrix phase is that it helps in propagation of brittle cracks from fibre to fibre. 4. Thermosetting Polymers can be used as matrix material while thermoplastic polymer cannot be used. The matrix phase binds the fibers together and acts as the medium by which an externally applied stress is transmitted and distributed to the fibers. The matrix protects the individual fibers from surface damage as a result of mechanical abrasion or chemical reaction with the environment. The matrix prevents the propagation of brittle cracks from fiber to fiber: metal, thermoplastic and thermosetting polymers are used as matrix materials


  9. a. Which of the following is true regarding alternating polyamide copolymer of glycerine and aminocaproic acid? (a) It is vulcanized rubber like polymer. (b) It is an example of natural rubber. (c) It is a polymer which can be used as a thermosetting polymer or thermoplastic polymer. (d) It is an example of biodegradable polymer. Nylon 2- Nylon 6 is an alternating copolymer of glycerine H,N -CH,-COOH] and amino caproic acid [H2N - (CH2)5 COOH] and it is biodegradable in nature.


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