Interview MCQ Set 1
1. Which of the following is used in electron microscope?
a) electron beams
b) magnetic fields
c) light waves
d) electron beams and magnetic fields
Answer: d [Reason:] Electron Microscope uses electron beams and magnetic fields to produce the image, whereas the light microscope uses light waves and glass lenses. In electron microscopy, a much higher resolution is obtained with extremely short wavelength of the electron beam.
2. Electron Microscope can give a magnification up to ___________
Answer: a [Reason:] The resolving power of the electron microscope is more than 100 times that of the light microscope, and it produces useful magnification up to 400,000X. It is possible to resolve objects as small as 10 Angstrom.
3. Which of the following are true for electron microscopy?
a) specimen should be thin and dry
b) image is obtained on a phosphorescent screen
c) electron beam must pass through evacuated chamber
d) specimen should be thin and dry, image is obtained on a phosphorescent screen and electron beam must pass through evacuated chamber
Answer: d [Reason:] Since electrons can travel only in high vacuum, the entire electron path through the instrument must be evacuated; specimens must be completely dehydrated prior to examination. Only very thin specimens can be observed in the conventional electron microscope since the penetrating power of electrons through matter is weak. The magnified image may be viewed on a phosphorescent or fluorescent screen.
4. Degree of scattering in transmission electron microscope is a function of __________
a) wavelength of electron beam used
b) number of atoms that lie in the electron path
c) number and mass of atoms that lie in the electron path
d) mass of atoms that lie in the electron path
Answer: c [Reason:] In a transmission electron microscope, contrast results from the differential scattering of electrons by the specimen, the degree of scattering being a function of the number and mass of atoms that lie in the electron path.
5. Negative Staining is used for examining _____________
a) virus particles
b) protein molecules
c) bacterial flagella
d) virus particles, protein molecules and bacterial flagella
Answer: d [Reason:] In negative-staining the electron opacity of the surrounding field is increased by using an electron-dense material such as phosphotungstic acid as a stain. Negative staining is particularly valuable for the examination of very small structures such as virus particles, protein molecules and bacterial flagella.
6. Which among the following helps us in getting a three-dimensional picture of the specimen?
a) Transmission Electron Microscope
b) Scanning Electron Microscope
c) Compound Microscope
d) Simple Microscope
Answer: b [Reason:] The scanning electron microscope lacks the resolving power obtainable with the transmission electron microscope but has the advantage of revealing a striking three -dimensional picture. The surface topography of a specimen can be revealed with clarity and a depth of field not possible by any other method.
7. The secondary electrons radiated back in scanning microscope is collected by?
c) vacuum chamber
Answer: b [Reason:] In scanning electron microscope (SEM), the surface of the specimen is irradiated with a very narrow beam of electrons. Such irradiations causes low energy (secondary) electrons to be ejected from the specimen which can then be collected on a positively-charged plate or anode thereby generating an electric signal.
8. On what factors do the intensity of secondary electrons depends upon?
a) shape of the irradiated object
b) chemical composition of the irradiated object
c) number of electrons ejected
d) size and chemical composition of the irradiated object, number of electrons ejected and on the number of electrons reabsorbed by surrounding
Answer: d [Reason:] The irradiations in SEM causes secondary electrons to be ejected from the specimen thereby generating a signal that is proportional to the number of electrons striking the anode. The intensity or the number of secondary electrons depends on the shape and the chemical composition of the irradiated object and also on the number of electrons ejected and the number of electrons reabsorbed by surrounding.
9. Where do we obtain the magnified image of the specimen in SEM?
a) cathode ray tube
b) phosphorescent screen
d) scanning generator
Answer: a [Reason:] In TEM, the image is obtained on a phosphorescent screen but in SEM the magnified image of the surface topography of the specimen is obtained on the cathode ray tube. The electronic signals generated scan the specimen in a raster pattern in the manner of a television system to produce an image on a cathode ray tube.
10. Which of the following techniques are used in Transmission Electron Microscopy (TEM) for examining cellular structure?
b) Shadow Casting
c) Ultrathin Sectioning
d) Negative-Staining, Shadow Casting, Ultrathin Sectioning, Freeze-Etching
Answer: d [Reason:] Numerous techniques are available for use with electron microscopy which extends its usefulness in characterizing cellular structure. Some of them are: Negative-Staining (which increases the electron opacity of surrounding), Shadow Casting (helps in producing three-dimensional structure of the object), Ultrathin Sectioning and Freeze-Etching.
Interview MCQ Set 2
1. The biosynthesis of proline takes place from ____________
a) aspartic acid
b) glutamic acid
c) pyruvic acid
d) alpha-keto glutaric acid
Answer: b [Reason:] The biosynthesis of proline takes place from glutamic acid in which the initial step utilizes metabolic energy in the form of ATP.
2. Which of the following acts as a precursor for the activation of peptidoglycan?
Answer: b [Reason:] Sugars such as acetylglucosamine are activated by the attachment of a UDP to form a sugar-UDP precursor which is a general method involved in the biosynthesis of peptidoglycan.
3. Bactoprenol is a ___________
a) membrane phospholipid
b) amino acid carrier
c) fatty acid
Answer: a [Reason:] Bactoprenol is a membrane phospholipid to which the AMA-UDP precursor is coupled during the synthesis of peptidoglycan.
4. Electrons entering the respiratory chain of chemoautotrophic bacteria enter the chain at higher potential.
Answer: a [Reason:] Electrons entering the respiratory chain from oxidation of inorganic substrates by chemoautotrophic bacteria usually enter the chain at a higher point than those electrons from the oxidation of organic substrates by chemoheterotrophs.Thus chemoautotrophs are at a considerable energetic disadvantage for this reason.
5. ATP dependent NADPH2 production is a process found in ______________
Answer: b [Reason:] Nitrobacter is a chemiautotrophic bacteria that follows the process of ATP-dependent-NADPH2 production for the production of NADPH2 to be used with ATP for carbon dioxide fixation.
6. Each turn of Calvin cycle results in the fixation of ________ molecule of carbon dioxide.
Answer: a [Reason:] Each turn of the Calvin cycle results in the fixation of one molecule of carbon dioxide. Carbon dioxide is fixed in a reaction with the acceptor molecule ribulose diphosphate.
7. The peptidoglycan layer of Staphylococcus aureus consists of a bridge between muramic acid peptides which is composed of?
Answer: d [Reason:] In Staphylococcus aureus a bridge composed of five glycine molecules can link two muramic acid peptides together.
8. Binding proteins for active transport systems of Gram-negative bacteria are associated with ____________
a) cell membrane
b) cytoplasmic membrane
c) periplasmic space
d) nuclear membrane
Answer: c [Reason:] Active-transport of Gram-negative bacteria are associated with binding proteins in the periplasmic space. The binding proteins have very high affinities for specific nutrients, including amino acids, sugars, and inorganic ions.
Interview MCQ Set 3
1. Polioviruses belongs to which of the following groups?
c) foot and mouth disease viruses
Answer: a [Reason:] Polioviruses belong to the enteroviruses because they are found in the intestines and excreted in the feces. They cause mainly intestinal infections and sometimes infections of the respiratory tract; neurological disease may also be produced.
2. Where does polioviruses multiply first?
c) lymph nodes
d) spinal cord
Answer: b [Reason:] Polioviruses multiply in the oropharynx or intestinal mucosa, pass to the lymphatic system and eventually reach the bloodstream.
3. The Sabin vaccine is 70 to 90 percent effective for immunization against poliomyelitis.
Answer: b [Reason:] The Salk virus is 70 to 90 percent effective and is administered in a series of three intramuscular injections.
4. At what pH values are the rhinoviruses destroyed?
Answer: c [Reason:] Rhinoviruses differ from enteroviruses by being destroyed at pH values of less than 5 (such as would occur in the stomach) and by having an optimal growth temperature at 33 degree C.
5. Complement- fixation is done for laboratory diagnosis of which of the following disease?
Answer: d [Reason:] Laboratory diagnosis of FMD is done by complement-fixation, virus-neutralization, or mouse-inoculation tests.
6. Eastern equine encephalitis is more fatal than western equine encephalitis.
Answer: a [Reason:] Eastern equine encephalitis has a high mortality rate (50 to 70 percent), whereas western equine encephalitis virus infections are seldom fatal (3%).
7. Yellow fever is caused by ____________
Answer: c [Reason:] Yellow fever is caused by flaviviruses which differs from others in causing a disease in which the liver, kidney, and other organs are affected.
8. Which of the following viruses consists of a helical nucleocapsid?
Answer: d [Reason:] Coronaviruses have a helical nucleocapsid and contain single-stranded RNA of the (+) type.
9. Which drug is used to cure influenza caused by type A strains?
Answer: b [Reason:] A synthetic drug, amantadine, can prevent and even help to cure influenza caused by type A strains; it acts by preventing the penetration and uncoating of the virus after it attaches to a host cell.
10. Which of the following is incorrect with respect to Paramyxoviruses?
a) large (125 to 250 nm)
b) core of single-stranded (—) RNA
c) rna is segmented
d) hemagglutinin and neuroaminidase activities occur together
Answer: c [Reason:] The paramyxoviruses are larger (125 to 250 nm), the RNA is segmented and only the (—) strand is present, and the hemagglutinin and neuroaminidase activities occur together in a single kind of surface glycoprotein (HN).
11. Crimean-Congo hemorrhagic fever is transmitted by _____________
c) biting flies
Answer: b [Reason:] Crimean-Congo hemorrhagic fever occurs in Africa and Asia and is spread by ticks. This disease is caused by Bunyaviruses.
12. What is the shape of the Rhabdoviruses?
c) brick shaped
Answer: a [Reason:] Rhabdoviruses are 70 to 80 by 130 to 240 nm in size and have a characteristic bullet shape. They have a helical nucleocapsid and contain single-stranded RNA of the (—) type.
Interview MCQ Set 4
1. From which of the following animal was the material isolated which was used for the vaccination for the first time?
Answer: b [Reason:] Jenner used the material isolated from cows to be used as a vaccination and it provided protection against natural smallpox infection.
2. Vaccination was invented by ____________
Answer: a [Reason:] In 1796 Jenner first vaccinated an 8-year old boy with material removed from cow and it gave protection against smallpox virus.
3. Causative agent of tobacco mosaic disease was filterable.
Answer: a [Reason:] In 1892, Dmitrii Ivanowski discovered that the causative agent of tobacco mosaic disease was filterable.Viruses that can pass through porcelain filters are known as filterable viruses.
4. Yellow fever virus can be attenuated by serial passage on cultures of ________________________
a) embryonated eggs
c) chick embryo tissue
d) pig embryo tissue
Answer: c [Reason:] Max Theiler found in 1937 that virulent yellow fever virus can be attenuated by serial passage on cultures of chick embryo tissue.
5. Effective poliomyelitis vaccines were developed by culturing the virus of poliomyelitis on the kidney cells of which animal?
Answer: b [Reason:] Enders, Robbins, and Weller laid the foundation for the development of effective poliomyelitis vaccines by culturing the virus of poliomyelitis on monkey kidney cells in 1949.
6. For which viral disease, vaccine has been recently developed through the use of tissue culture?
d) S mallpox
Answer: a [Reason:] Among the virus diseases for which vaccines have been recently developed through the use of tissue culture is measles (rubeola).
7. Rubella vaccines contain viruses are isolated only in African green monkey cells.
Answer: b [Reason:] Rubella vaccines contain viruses either isolated in African green monkey cells and attenuated by further cell passage (in primary duck embryo cells) or isolated and passed to diploid human embryo cells.
8. Translation of mRNA into proteins takes place in the ________________
a) host cell nucleus
b) host cell cytoplasm
c) viral nucleus
d) viral cytoplasm
Answer: b [Reason:] Translation of mRNA into proteins takes place in the host cell cytoplasm and uses ribosomes, transfer RNAs, and enzymes in the cytoplasm.
Interview MCQ Set 5
1. Which of the following sewerage systems carry domestic and industrial wastewater?
a) sanitary sewers
b) storm sewers
c) combined sewers
d) storm and combined sewers
Answer: a [Reason:] Sanitary sewers carry domestic and industrial wastewater for its ultimate treatment and disposal.
2. The more oxidizable organic material, the lesser the BOD.
Answer: b [Reason:] The magnitude of the BOD is related to the amount of organic material in the wastewater-i.e., the more oxidizable organic material, the higher the BOD.
3. Which of the following is a strict anaerobe?
Answer: d [Reason:] Methane producers are strict anaerobes e.g., Methanobacterium, Methanosarcina, Methanococcus. They produce methane and carbon dioxide as end products.
4. In which of the following treatment involve oxidation of organic constituents of the wastewater?
a) Primary treatment
b) Secondary treatment
c) Advanced treatment
d) Final treatment
Answer: b [Reason:] Secondary or biological treatment is done to adsorb and ultimately oxidize organic constituents of the wastewater, i.e, to reduce the BOD.
5. The upper region of the trickling filter is favorable for the growth of _____________
Answer: c [Reason:] The upper region of the trickling filter is favorable for the growth of algae, and at times their growth may become so extensive that it impairs the operation of the filter.
6. Activated sludge usually employs an aeration period of ________________
a) 1 hour
b) 24 hours
c) 10-15 hours
d) 4-8 hours
Answer: d [Reason:] The activated sludge process usually employs an aeration period of 4 to 8 hours, after which the mixture is piped to a sedimentation tank.
7. Oxidation ponds are very deep ponds.
Answer: b [Reason:] Oxidation ponds also called lagoons are shallow ponds which are 2 to 4 ft in depth designed to allow algal growth on the wastewater effluent.
8. Trickling filter is used in which of the following wastewater treatment processes?
a) Primary treatment
b) Secondary treatment
c) Advanced treatment
d) Final treatment
Answer: b [Reason:] The trickling filter is used in secondary treatment in which a stationary microbial culture is fed by a continuous supply of nutrients.It is used for filtration processes.
9. Belt filter presses are used in which of the following process?
Answer: c [Reason:] Dewatering is done by vacuum filters,belt filter presses and centrifuges and is often enhanced by the addition of polymer or other chemical coagulant aids.
10. Which of the following gases are produced in large amounts during sludge digestion?
Answer: a [Reason:] About 60-70% methane is produced during sludge digestion with smaller amounts of carbon dioxide,hydrogen and nitrogen.
Interview MCQ Set 6
1. Gas gangrene is caused by which of the following microorganisms?
a) Staphylococcus aureus
b) Clostridium perfringens
c) Pseudomonas aeruginosa
Answer: b [Reason:] Anaerobic bacteria, Clostridium perfringens, causes the wound infection gas gangrene.
2. The characteristic lesion, abscess caused by Staphylococcus aureus is a type of non-localized infection.
Answer: b [Reason:] The characteristic lesion, abscess caused by Staphylococcus aureus, is a walled-off cavity in the tissues containing the staphylococci, numerous white blood cells etc. This is a type of localized infection.
3. Which of the following condition is false for tissue invasion by C.perfringens?
a) anaerobic condition of the wound
b) production of large amounts of hydrogen gas
c) production of small amounts of hydrogen gas
d) release of toxins
Answer: c [Reason:] Production of large amounts of hydrogen gas by the bacteria contributes to the rapidity of tissue invasion.
4. Amputation is the only way to stop the spread of C.perfringens to the rest of the body.
Answer: a [Reason:] Amputation of an affected limb is often the only way to stop the spread of C.perfringens to the rest of the body.
5. What is the shape of the lymph nodes?
Answer: d [Reason:] Lymph nodes are ovoid structures ranging in size from one to several millimeters and are widely distributed throughout the body.
6. Lymph enters a lymph node by several _________________
a) lymphatic trunks
b) lymphatic vessels
c) lymphatic ducts
Answer: b [Reason:] Lymph enters a lymph node by any of several lymphatic vessels, passes through the lymph node along tortuous, winding channels, and emerges via a single efferent lymph vessel.
7. Which microbe causes the disease erysipelas?
a) S. pyogenes
b) C. perfringens
c) Pseudomonas aeruginosa
Answer: a [Reason:] Erysipelas, an inflammatory disease of the skin is caused by S. pyogenes. The painful lesions are spread by invasion of the lymphatic system of the subepidermal tissue.
8. Which of the following is not the characteristic of a bubo?
b) sore when infected
d) free from bacteria
Answer: c [Reason:] The lymph node removes nearly all of the bacteria that enters it, and it may become inflamed, enlarged, and sore when infected and in this condition it is sometimes called a bubo.
9. Where does Neisseria meningitidis reach after entering the body?
Answer: d [Reason:] Neisseria meningitidis present in the nasopharynx can reach the meninges (membranes that cover the brain and spinal cord) by means of a transient bacteremia.
10. Which of the following microorganism can cause acute renal failure?
b) Salmonella typhi
c) Neisseria meningitidis
d) Bacillus anthracis
Answer: a [Reason:] By means of a bacteremia, spirochetes of the genus Leptospira can reach the kidneys, where they may eventually cause acute renal failure.
11. Which of the following disease is caused by the pathogen directly infecting the lymphatic system?
b) typhoid fever
c) renal failure
Answer: b [Reason:] In typhoid fever, Salmonella typhi after penetrating through the epithelial cells, enter the lymphatic system, and reach the mesenteric lymph nodes.
12. Which of the following disease is an example of septicemic infection?
a) typhoid fever
d) renal failure
Answer: c [Reason:] Anthrax is an example of septicemic infection in which the number of Bacillus anthracis organisms may often exceed the number of erythrocytes in the blood.
Interview MCQ Set 7
1. What of these can be used as a reasonable model for measurement system capability studies? Here y,x and ε denote the observed measurement, true measurement, and the measurement error respectively.
Answer: b [Reason:] The reasonable model, which can be used for measurement system capability is expressed as,
2. The variance of the total observed measurement is expressed by _____
Answer: d [Reason:] The variance of the total observed measurement uses the value of the sum of the variances of product errors, and the gauge errors. It is calculated by,
3. The P/T ratio stands for ____
a) Probability to tolerance ratio
b) Precision to time ratio
c) Probability to total ratio
d) Precision to tolerance ratio
Answer: d [Reason:] The P/T ratio is used in the measurement system capability analysis. In P/T ratio, P/T refers to Precision to tolerance ratio.
4. What is the value of the P/T ratio?
Answer: b [Reason:] The P/T ratio is calculated for the evaluation of the gauge capability. It uses the value of the
The value of P/T ratio is given by,
5. If the number of standard deviations between the usual natural tolerance limits of a normal distribution, what is the value used for k in the P/T ratio?
Answer: c [Reason:] The value k=6 in the P/T ratio corresponds to the number of standard deviations, between the usual natural tolerance limits for a normal distribution.
6. For a process, which has, USL and LSL equal to 60, and 5 respectively, and the value of =0.887, what will be the value of P/T ratio when k=6?
Answer: d [Reason:] We know that,
Putting the values in the question, we get P/T=0.097.
7. Which of these indicate an adequate measurement system?
Answer: a [Reason:] If the value of P/T ratio is lesser than or equal to 0.1, the measurement system used is predicted to be adequate for the selected process.
8. The options are the P/T ratios for different measurement systems. Which of these shows an adequate measurement system?
Answer: d [Reason:] A P/T ratio lesser than 0.1 indicates an appropriate measurement system for any process. So here, 0.06<0.1, so it is an example of acceptable measurement systems.
9. The cause of calling a measurement system adequate because it has P/T ratio lesser than 0.1, is ___
a) A measurement device should be calibrated in units one-tenth large as the accuracy required in final measurement
b) A measurement device should be calibrated in units one-third large as the accuracy required in final measurement
c) A measurement device should be calibrated in units one-fourth large as the accuracy required in final measurement
d) A measurement device should be calibrated in units three-tenth large as the accuracy required in final measurement
Answer: a [Reason:] Values of estimated P/T ratio of 0.1 or less indicate adequate measurement system. It’s based upon the general rule, which requires the measurement device to be calibrated in units one-tenth large, as the accuracy required in the final measurement.
10. Which of these can be used as the estimate of standard deviation of total variability which is including both product variability, and the gauge variability?
a) The sample mean
b) The sample variance
c) The sample standard deviation
d) No of defects in the sample
Answer: b [Reason:] The sample variance can be used as the estimate of the standard deviation of the total variability, which includes both, the product variability, and the gauge variability.
11. If the sample variance of a process is, 10.05, and the gauge capability standard deviation is estimated to be 0.79. What will be the value of the estimate of the standard deviation of the product variability?
Answer: b [Reason:] As we know that,
12. Which of these show a correct expression for the ρp?
Answer: c [Reason:] The gauge capability ratio ρp
is the ratio of the variances of the product error and the gauge errors. It is expressed as,
13. The gauge capability ratio ρM is expressed as ____
Answer: b [Reason:] The value of gauge capability ratio ρM
is a ratio of the variances of the gauge errors and the total observed errors. It is expressed as,
14. The general rule, that is used to define a measurement system adequate by using P/T ratio equal to or less than 0.1, can be used without caution.
Answer: b [Reason:] The caution should be used in accepting this general rule of thumb in all cases. A gauge must be capable to measure product accurately enough and precisely enough, for the analyst to make a correct decision. This may not necessarily require P/T <=0.1
Answer: a [Reason:] It is known that,
Combining all three equations, we get,
Interview MCQ Set 8
1. EWMA and cusum charts can be used for the short production runs because ____
a) They are good in phase II
b) They have shorter ARL
c) They don’t detect process shift
d) They detect larger process shift
Answer: b [Reason:] EWMA charts and the cusum charts both, find applications in the short production run cases. This is due to the fact that the EWMA charts and the Cusum charts both have shorter ARL than the Shewhart charts.
2. Which of these is suitable for the short run environment?
a) x bar chart
b) R chart
d) Self starting cusum chart
Answer: d [Reason:] The Cusum charts are effective for subgroups size of one. The self starting version of the Cusum charts is particularly suitable for the short run environment due to the same fact.
3. Which of these is not one of the areas for which, the self starting cusum approach uses regular process measurements for?
a) For establishing the cusum
b) For calibrating the cusum
c) For acceptance sampling
d) For process monitoring
Answer: c [Reason:] The self starting approach of cusum charts uses regular process measurements for both establishing the cusum, and calibrating of cusum. These measurements are also used for process monitoring.
4. Which of these is eliminated by the self starting approach?
a) Phase I parameter estimation phase
b) Phase I parameter measurement phase
c) Phase II parameter estimation phase
d) Phase II parameter measurement phase
Answer: a [Reason:] The self starting approach uses regular process measurements for establishing and calibrating the cusum, and for process monitoring. Thus, this eliminates the phase I parameter estimation stage.
5. The false alarm rate is ___ when small number of subgroups is used for the Shewhart control charts.
c) Remains same
d) Changed randomly
Answer: b [Reason:] The number of subgroups used in calculating the trial control limits for Shewhart control charts, impacts the false alarm rate of the chart. This rate is inflated when small number if subgroups is used.
6. Who was the first person to study the effect of the number of subgroups used for x bar and R chart control limit calculation on the false alarm rate?
Answer: a [Reason:] The false alarm rate of the Shewhart control charts also depends over the number of subgroups used to construct the trial control limits. This was first studied by Hillier (1969).
7. Which of these charts can be used instead of Shewhart control charts, in the case of small number of subgroups used to construct the charts, which were recommended by Quesenberry?
Answer: d [Reason:] Quesenberry recommended the Q charts to be used in the place of the Shewhart control charts, in the case of small subgroup number used to calculate the control limits. This was because small number of subgroups used with Shewhart control charts, increased their FAR.
8. Which method was suggested by Del Castillo and Montgomery, to be used instead of the Q-chart to get better ARL performance?
a) Kalman Filter
b) Acceptance Sampling
c) Design of experiments
d) Deleting some samples completely
Answer: a [Reason:] Del Castillo and Montgomery found the ARL performance of the Q-charts very inadequate. So, they recommended the Kalman filter that has a better ARL performance than Q-chart.
9. Which of these is not a purpose for which control charts are produced for?
a) Control of the process
b) Reduction of variability
c) Increment of variability
d) Continuous process improvement
Answer: c [Reason:] The control charts are generally plotted for the main reasons like control of the process or statistical monitoring, reduction of variability, and continuous process improvement.
10. Which of these is used when the process has achieved high capability level?
a) Trial control limits
b) Actual control limits
c) Modified control limits
d) Easy control limits
Answer: c [Reason:] At the stage, when the process has achieved a high level of capability, there is some relaxation provided to the level of the surveillance provided. This is generally done with modified control limits in the case of x charts.
11. Which of these is not a name of Modified control limits for x̅ charts?
a) Acceptance limits
b) Reject limits
c) Reserve limits
d) Liquid limits
Answer: b [Reason:] The relaxation in the case of x charts in the case of high process capability is provided with the use of the modified limits. These are also called reject limits.
12. Which of these is a method used when the process capability is quite high?
a) Acceptance sampling
b) Design of experiments
c) Acceptance control charts
d) Shewhart control charts
Answer: c [Reason:] When the process capability becomes very high, the relaxation of the level of surveillance is provided by using two methods; first is the reject limits, and the second is the acceptance control chart.
13. Which of these does not say that the modified control limits must be applied?
b) Process spread is considerably small
c) Natural variability becomes high
d) Process capability becomes quite good
Answer: c [Reason:] The modified control limits are used when the process capability is very high. The PCR Cpk≫1, very less process spread, and low natural variability indicate the high process capability. So, modified control charts are used in these conditions.
14. The six-sigma approach when implemented for a long time, the process may need modified control charts.
Answer: a [Reason:] As six-sigma approach to variability reduction focuses on improving process until the minimum value of Cpk=2. So this means high process capability, which encourages modified control charts usage.
15. If the Cpk=0.9899, the usage of modified control charts is very necessary.
Answer: b [Reason:] The modified control charts have the use of the modified control limits, which are used when the process capability is high or Cpk≫1. As Cpk=0.9899, the usage of modified control charts is not necessary.