Skip to main content

Composite materials Viva Question and Answers

Also Read


Q1- What is a composite?
a. Recycled waste
b. A chemical reaction
c. The latest computer software
d. A structural material consisting of two or more constituents. 

Answer:
A composite is a structural material which consists of combining two or more constituents

Q2- Advanced composites are
a. naturally found
b. traditionally used in aerospace industries
c. low performance composites
Answer:
Advanced composites are traditionally used in aerospace industries 

Q3- Composites are easy to repair
a. True
b. False
Answer: 
Composites are generally difficult to repair 

Q4- What fiber factors contribute to the mechanical performance of a composite?
a. Length
b. Orientation
c. Shape
d. All of the above
Answer: 
Length, orientation, and shape all contribute to the mechanical performance of a composite 

Q5- PMC stands for:
a. Polymer Metal Composition
b. Polymer Matrix Composite
c. Polyethylene Metal Composition
Answer: 
PMC stands for Polymer Matrix Composite 

Q6-The most common advanced composites are
a. Metal Matrix Composites
b. Polymer Matrix Composites
c. Ceramic Matrix Composites
Answer: 
The most common advanced composites are Polymer Matrix Composites

Q7- The most common fibers used in advanced polymer composites are
a. glass, steel, and aluminum
b. glass, graphite, and kelvar
c. glass, steel, and kelvar
Answer: 
The most common fibers used in advanced polymer composites are glass, graphite, and kelvar

Q8- E-glass type fiber is used for
a. Electrical applications
b. Environmental applications
c. Evaporative applications
Answer: 
E-glass type fiber is used for electrical applications

Q9- One of the major drawbacks of composites is
a. high cost of fabrication
b. no body needs them
c. they are extremely heavy
Answer: 
One of the major drawbacks of composites is their relatively high cost of fabrication

Q10- SMC stands for
a. Structural Metal Composite
b. Strong Metal Composite
c. Sheet Molding Compound
Answer: 
SMC stands for Sheet Molding Compound

Q11- Annual growth of composites is at a steady rate of
a. 5 percent
b. 10 percent
c. 15 percent
d. -15 percent
Answer: 
Annual growth of composites is at a steady rate of 10 percent

Q12- Reducing one pound of mass in a commercial aircraft can save up to how many gallons per year?
a. 50
b. 350
c. 3500
d. 30000
Answer: 
Reducing one pound of mass in a commercial aircraft can save up to 350 gallons per year?

Q13- The material of the fiber directly influences the mechanical performance of a composite
a. True
b. False
Answer: 
The material of the fiber directly influences the mechanical performance of a composite

Q14- The most common fiber shape is
a. Rectangular
b. Triangular
c. Circular
Answer: 
The most common fiber shape is circular

Q15- The units of fracture toughness are
a. MPa-m
b. MPa^0.5-m
c. MPa-m^0.53
Answer: 
The units of fracture toughness are MPa-m^0.5

Q16- A typical range of carbon content in carbon fiber is
a. 93-95%
b. 92-95%
c. 93-94%
d. 90-95%

Answer: 
A typical range of carbon content in carbon fiber is 93-95%

Q17- Graphite fibers have one of the following carbon content
a. 99%
b. less than 99%
c. more than 99%
d. 98%3
Answer: 
Graphite fibers have more than 99% carbon content

Q18- Thermoset plastic polymers have the following type of bonding
a. Covalent bond
b. Vanderwaals bond
c. Atomic bond
d. none of the above

Answer: 
Thermoset plastic polymers have Vanderwaals type bonding

Q19- Current service temperature limits for polymers reach
a. 750 degrees Fahrenheit
b. 1750 degrees Fahrenheit
c. 450 degrees Fahrenheit
d. 350 degrees Fahrenheit

Answer: 
Current service temperature limits for polymers reach 750 degrees Fahrenheit 

Q20- Mechanical fasteners are made of what type of composite
a. Boron-Epoxy
b. Graphite-Epoxy
c. Carbon-Carbon
d. All of the above
Answer: 
Mechanical fasteners are made of Carbon-Carbon composites

Q21- Isotropic means
a. a material with different properties in all directions
b. a material with the same properties in all directions
c. a material with elastic properties
d. none of the above
Answer: 
Isotropic means a material with the same properties in all directions

Q22- Composite materials are
a. isotropic but not homogeneous
b. homogeneous but not isotropic
c. both homogeneous and isotropic
d. neither homogeneous or isotropic
Answer: 
Composite materials are neither homogeneous or isotropic

Q23- Anisotropic materials are
a. materials with different properties in all directions
b. materials with the same properties in all directions
c. materials with the same properties in two perpendicular directions
d. none of the above
Answer: 
Anisotropic materials have different properties in all directions

Q24- Inter-ply hybrid composites consist of
a. two or more different composite systems
b. two or more different fibers used in the same ply
c. both a and b
d. none of the above
Answer: 
Inter-ply hybrid composites consist of two or more different composite systems

Q25- Aramid fibers are made up of
a. Carbon, Hydrogen, Oxygen and Graphite
b. Carbon, Hydrogen, Oxygen and Nitrogen
c. Carbon, Hydrogen, Oxygen
d. Carbon, Hydrogen, Nitrogen
Answer: 
Aramid fibers are made up of Carbon, Hydrogen, Oxygen and Nitrogen

Q26- A typical example of thermoplastics include
a. polyethylene
b. polyesters
c. phenolics
Answer: 
A typical example of thermoplastics include polyethylene

Q27- Polymer matrix composites are manufactured in the automotive industry where short production runs are necessary by
a. filament winding
b. autoclave forming
c. resin transfer molding
d. none of the above
Answer: 
Polymer matrix composites are manufactured in the automotive industry where short production runs are necessary by resin transfer molding

Q28- Which of the following composites are replacing metals in golf club shafts
a. Carbon-Carbon
b. Graphite-Epoxy
c. Boron-Epoxy
d. none of the above
Answer: 
Graphite-Epoxy is replacing metals in golf club shafts

Q29- Which of the following is a drawback for phenolic resin systems
a. high cost
b. low mechanical strength
c. high void content
d. brittleness
Answer: 
High cost is a drawback for phenolic resin systems

Q30- Bullet proof vests use
a. Kelvar
b. Graphite
c. Boron
d. Glass
Answer: 
Bullet proof vests use Kelvar

Q31- High performance applications in the aerospace industry use
a. Graphite
b. Boron
c. Kelvar 49
d. Kelvar 293
Answer: 
High performance applications in the aerospace industry use Kelvar 49

Q32- Thermoset polymers show which of the following
a. Decompose on heating
b. Soften on heating
c. Harden on heating
d. none of the above
Answer: 
Thermoset polymers decompose on heating

Q33- The performance indicator for buckling of a rod under a compressive load is
a. Young's modulus / density
b. (Young's modulus ^ 0.5) / density
c. (Young's modulus ^ 0.3333) / density. 

Answer: 
The performance indicator for buckling of a rod under a compressive load is (Young's modulus ^ 0.5) / density

Q34- Specific modulus is given by
a. Square root of Young's modulus / density
b. Strength / density
c. Young's modulus / density
Answer: 
Specific modulus is given by Young's modulus / density

Q35- Glass fibers are made from
a. slice glass
b. vapor deposition method
c. graphite
Answer: 
Glass fibers are made from slice glass

Q36- Which polymer is not desirable for smoke emmision?
a. Phenolic
b. Epoxy
c. Polyester
d. Polymide
Answer: 
Polymide is not desirable for smoke emmision

Q37- Which polymer has the maximum strength?
a. Phenolic
b. Epoxy
c. Polyester
d. Polymide
Answer: 
Epoxy has the maximum strength

Q38- Which polymer has the highest service temperature?
a. Phenolic
b. Epoxy
c. Polyester
d. Polymide4
Answer: 
Polymide has the highest service temperature




Comments

Post a Comment

Recent posts

Welding VIVA question and answers

VIVA QUESTIONS : Q1: Define welding? Ans:  Welding is a fabrication process that joins two or more materials, typically metals or thermoplastics, by melting and fusing them together using heat or pressure. Q2: What is the typical thickness of MS Plate used in general welding workshop experiments? Ans:  The thickness of the MS (Mild Steel) plate used in general welding workshop experiments can vary depending on the specific requirements of the experiment. However, commonly used thicknesses range from 3 mm to 12 mm. Q3: What is the common job material used in welding experiments? Ans:  The common job material used in welding experiments is mild steel. It is widely available, affordable, and relatively easy to work with, making it suitable for various welding applications and practice. Q4: What is the main function of an electrode in welding? Ans:  The main function of an electrode in welding is to carry the electric current necessary for the welding process and to ...
6 comments
Complete post >>

Fluid mechanics VIVA QUESTIONS and ANSWERS

1. Define density? Ans: It is defined as the ratio of mass per unit volume of the fluid. 2. Define viscosity? Ans: It is defined as the property of fluid which offers resistance to the movement of fluid over another adjacent layer of the fluid. 3. Differentiate between real fluids and ideal fluids? Ans: A fluid, which is in-compressible and is having no viscosity, is known as ideal fluid while the fluid, which possesses viscosity, is known as real fluid. 4. What is a venturimeter? Ans: It is a device which is used for measuring the rate of flow of fluid flowing through pipe. 5. What is a notch? Ans: A notch is a device used for measuring the rate of flow of a fluid through a small channel or a tank. 6. Define buoyancy? Ans: When a body is immersed in a fluid, an upward force is exerted by the fluid on the body. This upward force is equal to the weight of the fluid displaced by the body. 7. Define meta-centre? Ans: It is defined as the point about which a body...
14 comments
Complete post >>

Welding-LAP JOINT

Ex. No :                                                                              Date : LAP JOINT Aim To join the given two work pieces as a lap joint by arc welding. Material used Mild Steel plates. Tools required Welding power supply  Flat file Welding rod Chipping hammer Electrode holder Wire brush Gloves and apron Earthing clamps Shield and goggles Procedure The given workpieces are thoroughly cleaned, i.e. rust, scales are removed and the  edges are filed. The electrode is held in an electrode holder and ground clamp is clamped to the  welding plates and the power is supplied. The workpieces are positioned on the table to form a “Lab joint”. The tag weld is done on the both the ends of joining plates to avoid the m...
7 comments
Complete post >>

TIN SMITHY & Sheet metal

TIN SMITHY Introduction : Many engineering and house articles such as boxes, cans, funnels, ducts etc. are made from a flat sheet of metal. The process being known as tin smithy. For this the development of the article is first drawn on the sheet metal, then cut and folded, to form the required shape of the article. Allowance should be given in the drawing stage for folding and bending. This allowance depends upon the radius of the bend and thickness of the sheet metal. Sheet Metal Materials : A variety of metals are used in a sheet metal shop such as galvanized Iron, black, Iron, tin, Stainless Steel, copper and Aluminium. Hand Tools : The common hand tools used in sheet metal work are steel, try square, Wire gauge, Scriber, Ball peen hammer, Nylon Mallet, Snips Divider, Stakes, Cutting plier and Soldering Iron. Here, the details of tools that are being equipped by our workshop purpose only are presented. Wire Gauge: The thickness of sheet is referred in numbers known ...
5 comments
Complete post >>

Carpentry Viva Questions

Q1: Define carpentry? Ans:  Carpentry is a skilled trade that involves working with wood to construct, install, and repair structures and objects. It encompasses various tasks such as measuring, cutting, shaping, joining, and finishing wood to create functional and aesthetically pleasing products. Q2: What are the various types of wood material used in carpentry? Ans:  The various types of wood materials used in carpentry include softwoods (such as pine, fir, cedar, and spruce) and hardwoods (such as oak, maple, mahogany, and walnut). Other wood materials used in carpentry can include plywood, particleboard, MDF (medium-density fiberboard), and engineered wood products like laminated veneer lumber (LVL) and oriented strand board (OSB). Q3: What is the sequence of operations in carpentry? Ans:  The sequence of operations in carpentry typically involves planning and design, material selection and preparation, measuring and marking, cutting and shaping, joinery or fasteni...
1 comment
Complete post >>

sheet metal rectangular tray making

Aim :- To make a rectangular tray from a given metallic sheet. Tools Required MALLET Snip Stake STEEL RULE Ball peen HAMMER Straight EDGE RIVETS Scriber Procedure The given metal sheet is smoothed using mallet. The measurements of rectangular tray (tray development drawing) is drawn on the sheet with given dimensions using the scriber and steel rule. The sheet is cut as per the marked dimensions by straight snips. Fold or bend as per the given order using mallet and stake. Bending is done as per the given dimension using the stake and mallet. Rivet the folded sheet by using the given rivets and hammer. Safety Precautions Each cut you make exposes sharp edges and creates burrs that can slice a finger. Must Use Hand gloves when cutting the sheet. Metal waste also has hazardous edges. So...
1 comment
Complete post >>

SINGLE ‘V’ BUTT JOINT

Experiment No.:                                                                                      Date: SINGLE ‘V’ BUTT JOINT Aim: To prepare a single ‘V’ Butt Joint as per dimensions given in the sketch. Material Required: Mild Steel plates: 80mm X 40mm X 6mm = 2 Nos Mild Steel electrode ¢ 3.15 mm Equipment required: A.C. Transformer with all welding accessories like Electrode holder, cables. Tool Required: Steel rule 300mm  Scriber 150mm Flat file 300mm Try square 200mm Flat Tong 450mm  Chipping hammer 200mm Ball peen hammer 750mm  Wire brush Welding screen Sequence of Operations: 1. Marking  2. Filing  3. Welding  4. Finishing Procedure: Take two Mild steel plates of size 80mm X 40mm X 6mm. Fix the wor...
2 comments
Complete post >>

Strength of Materials viva Question and Answers

1. Define Hooke’s Law.  Ans . It states that when the material is loaded within the elastic limit the stress is directly proportional to strain. i.e. Stress α strain. or Stress = constant x Strain 2. Define Strength of materials.   Ans . The strength of a material is its ability to withstand an applied stress without failure. 3. What is stress?  Ans . When load is applied on any object then a resisting force is induced, that resisting or reacting per unit area of cross-section is called stress. 4. What is strain? Ans . Stress is change in dimensions upon original dimentions. 5. What is deformation?  Ans . Deformation is change in dimensions of any object due to applied load. 6. On which steel you have performed tension test. What is its carbon content?  Ans . On mild steel (0.3 to 0.6% carbon). 7. What kind of fracture has occurred in tensile specimen.  Ans . Ductile fracture. 8. Define temperature stress. Ans . Stress introduc...
Post a Comment
Complete post >>

Sheet metal Funnel making

Making a Funnel using metallic sheet Making a Funnel using metallic sheet Aim:- To make a funnel from a given (GI)metallic sheet. Tools Required:- MALLET, SNIP, STAKE, STEEL RULE, BALL PEEN HAMMER, STRAIGHT EDGE, RIVETS, SCRIBER Procedure:  The size of the given sheet metal is checked for its dimensions using a steel rule The required development of surface is being made on the white paper which is overlapped on the sheet metal. The marking is done on the sheet metal as per the development being done on the paper. Now using straight snips, unwanted materials are removed. Now fold and bend the workpiece to make the funnel shape and joint is made on the workpieces. Then using a groover, a locked grooved joint is made for about 5mm. Also, hemming is done in the bottom of the funnel. In between top face and bottom face, a butt joint is made using a solder. Finally, trimming and finishing operations are carried out. Safety Precautions:- Each cut you make exposes s...
Post a Comment
Complete post >>

SolidWorks Practice parts

Solidworks practice parts Click here to view step by step process to make these basic shapes using solidworks Exercise 1 Exercise 2 Exercise 3 Exercise 4 Exercise 5 Exercise 6 Exercise 7 Exercise 8 Exercise 9 Exercise 10 Exercise 11 Exercise 12 Exercise 13 Exercise 14 Exercise 15 Exercise 16 Exercise 17 Exercise 18 Exercise 19 Exercise 20 Exercise 21 Exercise 22 Click here to view step by step process to make this shape using solidworks
6 comments
Complete post >>

Search This Blog