McqMate
101. |
Which of the following is true for the multiple start screw threads? |
A. | it is produced by a single helical groove |
B. | grooves should be different in spacing |
C. | it gives a quick transverse |
D. | it is formed in a transverse section on a cylinder |
Answer» C. it gives a quick transverse | |
Explanation: multiple start screw threads is produced by forming two or more than two helical grooves, equally spaced and similarly formed in an axial section on a cylinder. this gives a ‘quick traverse’ without sacrificing core strength. |
102. |
Statement 1: Flank angle of symmetrical thread is known as thread’s half-angle. Statement 2: It is measured parallel to the axis of a thread. |
A. | t, f |
B. | f, f |
C. | t, t |
D. | f, t |
Answer» A. t, f | |
Explanation: in a screw thread the angles between individual flanks and perpendicular to the thread axis which passes through the vertex of the fundamental triangle are called flank angles. the flank angle of a symmetrical thread is called as the half-angle of a thread. |
103. |
Flanks of the threads connect the crest with the roots. |
A. | true |
B. | false |
Answer» A. true | |
Explanation: flanks of thread are straight edges which connect the crest and the root. angle of thread is the angle between the flanks or slope of the thread measured in an axial plane and also known as the included angle. |
104. |
What is the effect of improper alignment of each tooth? |
A. | tooth thickness increases |
B. | face width decreases |
C. | load will not distributed evenly |
D. | pitch of teeth reduced |
Answer» C. load will not distributed evenly | |
Explanation: good alignment of each tooth on a gear is essential, as otherwise the load will not be distributed evenly over its face. it is quite probable that the load may be carried by one edge only introducing high bearing stresses, if teeth of a gear are machined poorly. |
105. |
Which of the following is not true about concentricity of teeth? |
A. | fluctuating velocity will be noticed when not concentric |
B. | can be checked by using projector |
C. | inaccuracy of parts when not concentric |
D. | should be tested to ensure the proper heat treatment |
Answer» D. should be tested to ensure the proper heat treatment | |
Explanation: concentricity of teeth is an important item and should be checked to ensure that the set up and equipment is in good order. when teeth are not concentric then fluctuating velocity will be noticed on the pitch line while transmitting motion. |
106. |
Which of the following option is true about an analytical method of inspection of gears? |
A. | analytical method is widely used for industries |
B. | this method is fast |
C. | all individual elements of gear teeth are checked |
D. | more accurate |
Answer» C. all individual elements of gear teeth are checked | |
Explanation: analytical method is slow and |
107. |
Which of the following element is not determined by analytical inspection? |
A. | profile |
B. | composite vibrations |
C. | spacing |
D. | pitch |
Answer» B. composite vibrations | |
Explanation: the analytical inspection of the gears consists in determination of these profile, spacing, pitch, backlash, runout or eccentricity or concentricity, thickness of tooth and lead. these teeth elements in which the errors are caused due to manufacturing errors are determined by analytical inspection. |
108. |
Statement 2: Gear blank should be tested for dimensional accuracy. |
A. | t, f |
B. | f, f |
C. | f, t |
D. | t, t |
Answer» D. t, t | |
Explanation: the gear blank should be tested for dimensional accuracy and eccentricity as outside diameter forms the datum from where the tooth thickness is measured, it forms an important item to be controlled. it is quite probable that the load may be carried by one edge only introducing high bearing stresses, if teeth of a gear be machined poorly. |
109. |
Which of the following is not determined by the functional type of inspection? |
A. | lead |
B. | noise level |
C. | variation in action |
D. | vibration |
Answer» A. lead | |
Explanation: the functional inspection consists of carrying out the running test of gear with another gear which is more accurate and is known as master gear or control gear, to determine composite vibration, noise level, or variation in action. |
110. |
Which of the following statement is true about inspection of gear? |
A. | profile is determined by functional inspection |
B. | backlash is determined by analytic inspection |
C. | analytic test require running test of gear |
D. | thickness of tooth is measured by functional inspection |
Answer» B. backlash is determined by analytic inspection | |
Explanation: functional type of inspection is done by running test of gear with another gear. it is used to determine noise level and composite variation. analytical method is used to determine backlash, lead and runout. |
111. |
Which of the following machine is used for rolling tests? |
A. | parkson gear tester |
B. | tooth caliper |
C. | base pitch measuring instrument |
D. | involute profile testing machine |
Answer» A. parkson gear tester | |
Explanation: rolling test is generally performed on parkson gear tester. this test reveals any errors in pitch, tooth form and concentricity of pitch line. any of the above errors will cause the variation of centre distance, when two gears are in mesh with each other. |
112. |
If reference circle of gear is eccentric then which error is reflected by this eccentricity? |
A. | cyclic error |
B. | periodic error |
C. | pitch error |
D. | undulation |
Answer» C. pitch error | |
Explanation: it must be emphasised that there are some in-built limitations in the gear itself while the accuracy of measurement of gear depends upon the measuring equipment available, such as the inability of a gear to define its own axis of rotation. thus if the reference circle of gear is eccentric, it would be reflected in pitch error. |
113. |
Statement 2: Accuracy of individual elements is necessary for precision gears. |
A. | t, f |
B. | f, f |
C. | t, t |
D. | f, t |
Answer» D. f, t | |
Explanation: the accuracy of any gear mainly depends upon the cutter accuracy and the setting of the machine. optical projection and rolling tests will suffice for most of the gears. it is necessary to determine the accuracy of individual elements in the manufacture of high precision gears. |
114. |
best method for examining the surface finish. Visual, touch and scratch inspection methods are not as accurate as microscopic. In these methods, minute flaws can’t be detected. |
A. | 0.0001 mm |
B. | 0.001 mm |
C. | 0.01 mm |
D. | 0.1 mm |
Answer» C. 0.01 mm | |
Explanation: touch inspection method can tell which surface is rougher. in this method, the finger-tip is moved along the surface at a speed of about 25/sec and the irregularities of about 0.01 mm can be easily detected. |
115. |
Which of the following material is not used for rubbing on the surface to be inspected in scratch inspection? |
A. | softer material |
B. | hard material |
C. | plastic |
D. | lead babbitt |
Answer» B. hard material | |
Explanation: in scratch inspection method, a softer material like plastic or lead babbitt is rubbed over the surface to be inspected. it carries the impression of the scratches on it which can be easily visualised. |
116. |
Statement 2: Direct instrument measurement is enabled to determine a numerical value of surface finish. |
A. | f, t |
B. | t, f |
C. | f, f |
D. | t, t |
Answer» A. f, t | |
Explanation: the main limitation of the method of inspection by touch is that the degree of surface roughness can not be assessed by this and also the minute flaws can’t be detected by the only touch. |
117. |
What is the limitation of microscopic inspection to check surface finish? |
A. | an average value is needed |
B. | small portion of surface can be detected at a time |
C. | a master finish surface is also needed |
D. | it is necessary to inspect whole surface together |
Answer» B. small portion of surface can be detected at a time | |
Explanation: microscopic inspection method have some limitation that at a time only a small portion of the surface can be inspected. so for inspection, several readings are required in this method to get an average value. |
118. |
In the method of microscopic inspection what is the angle of beam light with the work? |
A. | 200 |
B. | 300 |
C. | 600 |
D. | 900 |
Answer» C. 600 | |
Explanation: in one method of microscopic inspection, a straight edge is placed on the surface to be inspected and a beam of light is projected at about 60 degree to the work. the shadows cast into the surface scratches are magnified and studied. |
119. |
Which of the following is true for a method of measurement of surface finish with surface photographs? |
A. | different type of illumination is needed |
B. | no effect of type of illumination |
C. | same type of illumination is needed |
D. | monochromatic light is needed |
Answer» A. different type of illumination is needed | |
Explanation: in the method of surface inspection with magnified photographs of the surface are taken with different types of illumination. after this photographs with different illumination are studied and compared. |
120. |
In case of vertical illumination in measuring surface finish with surface photographs, which will appear as bright area? |
A. | flat portion |
B. | scratch |
C. | irregularity |
D. | hills |
Answer» A. flat portion | |
Explanation: in the inspection of surface with photographs if we use vertical illumination, then irregularities and scratches appear as dark spots and flat portion of the surface as bright area. but in case of oblique illumination, the case is reverse. |
121. |
Which of the following method use pendulum in measuring the surface finish? |
A. | micro interferometer |
B. | wallace surface dynamometer |
C. | reflected light intensity method |
D. | microscopic inspection |
Answer» B. wallace surface dynamometer | |
Explanation: wallace surface dynamo meter is like a friction meter which consists a pendulum in which the testing shoes are present which are clamped to a bearing surface and a spring pressure which is predetermined can be applied. |
122. |
Which of the following is not true for the method of measurement of surface finish by micro interferometer? |
A. | optical flat is used |
B. | monochromatic source of light is used |
C. | depth of defect can’t be measured |
D. | interference lines plays an important role in identification of the defect |
Answer» C. depth of defect can’t be measured | |
Explanation: in the method of inspection of surface by using micro interferometer, an optical flat is used which is placed on the surface to be examined and illuminated by using monochromatic light. interference bands are studied by using a microscope. |
123. |
Which of the following is the direct measure of surface finish in Wallace surface dynamometer? |
A. | time of swing |
B. | angle of swing |
C. | length of swing |
D. | height of swing |
Answer» A. time of swing | |
Explanation: in the case of wallace surface dynamometer, if the surface to be tested is smooth, there will be less friction and pendulum swings for a longer time period. so, time of swing of pendulum is a direct measure of surface finish. |
124. |
Which of the following is a destructive method in measuring surface finish? |
A. | gloss measurement |
B. | taper sectioning |
C. | diffraction technique |
D. | micro interferometer |
Answer» B. taper sectioning | |
Explanation: in taper sectioning method, a section is cut through the surface to be inspected at a shallow angle, thus magnifying height variations by a factor of cot theta, and the section is studied by optical microscope. it is an accurate but destructive method. |
125. |
In which type of system does power transmission takes place through compressed air? |
A. | fluid power system |
B. | hydraulic system |
C. | pneumatic system |
D. | stepper motors |
Answer» C. pneumatic system | |
Explanation: pneumatic system is a power transmission system in which, the transmission of power takes place through compressed air. the mechanical energy is given to compressor, that is, the shaft of the compressor is rotated by any means of the prime mover. the fluid power system is a power transmission system in which, the transmission of power takes place by means of “oil under pressure” or “compressed air”. if “oil under pressure” is used in the system for power transmission then the system is called a hydraulic system. |
126. |
The compressed air flows to the actuator through |
A. | pipes and valves |
B. | shafts |
C. | motors |
D. | flow control valve |
Answer» A. pipes and valves | |
Explanation: compressor drives air from the atmosphere and the compressed air flow through actuator through pipes and valves. |
127. |
The compressed air is delivered to the pneumatic system through the air compressor. |
A. | true |
B. | false |
Answer» A. true | |
Explanation: the air compressor draws the air from the atmosphere, compresses it and delivers the compressed air to the pneumatic system. compressor drives air from the atmosphere and the compressed air flow through actuator through pipes and valves. |
128. |
What is the function of the air dryer? |
A. | removes dirt |
B. | removes moisture |
C. | controls the rate of flow |
D. | controls the pressure |
Answer» B. removes moisture | |
Explanation: the compressed air delivered by the compressor contains moisture from the atmosphere. this moisture is separated and removed by the air dryer. only the dry compressed air is given to the pneumatic system. |
129. |
Which part of the Pneumatic system stores the compressed air? |
A. | air dryer |
B. | air compressor |
C. | air receiver tank |
D. | air lubricator |
Answer» C. air receiver tank | |
Explanation: the air receiver tank stores the compressed air. apart from storing the compressed air, it has several other functions also. it acts as cooler to cool the hot compressed air. it acts as moisture separator to separate and remove the water. |
130. |
Which type of pumps can give discharge even at high pressure? |
A. | multistage pumps |
B. | monoblock pumps |
C. | rotary pumps |
D. | single stage pumps |
Answer» C. rotary pumps | |
Explanation: rotary pumps are positive displacement pumps. rotary pumps have two or more rotating components. the discharge of rotary components remains almost the same irrespective of pressure. they can give discharge even at high pressure. in the other options, the type of pumps mentioned is all non-positive displacement types. |
131. |
Which type of component in the hydraulic system supports less vibration and noise? |
A. | flow control valve |
B. | oil reservoir |
C. | rotatory pumps |
D. | pressure gauge |
Answer» C. rotatory pumps | |
Explanation: very less vibration and noise are observed in the case of rotary pumps. these pumps are compact with very a smaller number of moving components. the flow control valves, oil reservoir and pressure gauge are the other parts of the hydraulic system with different functions. |
132. |
Hydraulic systems are slower in operation. |
A. | true |
B. | false |
Answer» A. true | |
Explanation: as oil has more viscosity, it cannot flow fast. hence hydraulic systems are slower in operation. hydraulic oils are petroleum based oils, they are inflammable and there is every chance of fire hazard if this is neglected. |
133. |
What prevents the leakage of oil inside an unbalanced vane pump? |
A. | vanes |
B. | cylindrical rotor |
C. | screw |
D. | difference between the pressure of inlet and outlet |
Answer» A. vanes | |
Explanation: the vanes are seated in the radial slots of the rotor and held against the casing by spring force or hydraulic force. hence there will not be any leakage of oil between the vane tips and the casing. still, there is a little amount of leakage and hence the volumetric efficiency will be around 95%. |
134. |
Which among the following are not the main selection criteria for selection of hydraulic pumps? |
A. | discharge |
B. | pressure |
C. | speed |
D. | weight |
Answer» D. weight | |
Explanation: the weight is not the main selection criteria for selection of hydraulic pumps. there are different values for gear pumps, vane pumps and piston pumps for pressure, discharge and speed which are predefined values. |
135. |
Which is the cheapest device for measuring flow / discharge rate. |
A. | venturimeter |
B. | pitot tube |
C. | orificemeter |
D. | none of the mentioned |
Answer» C. orificemeter | |
Explanation: orificemeter is the cheapest available device for measuring flow/discharge rate. |
136. |
The principle of Orificemeter is same as that of Venturimeter. |
A. | true |
B. | false |
Answer» A. true | |
Explanation: the working principle for both orificemeter and venturimeter is same. |
137. |
The Orificemeter readings are more accurate than Venturimeter. |
A. | true |
B. | false |
Answer» B. false | |
Explanation: the venturimeter readings are more accurate than orificemeter. |
138. |
The Orificemeter readings are more accurate than Pitot tube readings. |
A. | true |
B. | false |
Answer» B. false | |
Explanation: the pitot tube readings are more accurate than orificemeter. |
139. |
The Orificemeter has a smooth edge hole. |
A. | true |
B. | false |
Answer» B. false | |
Explanation: the orificemeter has a rough edge hole. |
140. |
A nanometre is connected to a section which is at a distance of about 4 to 6 times the pipe diameter upstream from orifice plate. |
A. | true |
B. | false |
Answer» B. false | |
Explanation: a manometre is connected to a section which is at a distance of about 1.5 to |
141. |
Venturimeter is based on integral form of Euler’s equation. |
A. | true |
B. | false |
Answer» A. true | |
Explanation: venturimeter is based on bernoulli’s equation. |
142. |
Orifice Meter can only be used for measuring rate of flow in open pipe like structure. |
A. | true |
B. | false |
Answer» A. true | |
Explanation: orificemetre can only be used for measuring rate of flow in an enclosed pipe like structure. |
143. |
Orifice meter consists of a flat rectangular plate. |
A. | true |
B. | false |
Answer» B. false | |
Explanation: orifice meter consists of a flat circular plate. |
144. |
TOPIC 5.3 TEMPERATURE: BIMETALLIC STRIP, THERMOCOUPLES |
A. | strain |
B. | pressure |
C. | displacement |
D. | voltage |
Answer» C. displacement | |
Explanation: bimetallic element is used for measuring temperature, it produces proportional output displacement for input temperature. |
145. |
Which of the following can be used for measuring temperature? |
A. | metallic diaphragm |
B. | fluid expansion system |
C. | capsule |
D. | bourdon tube |
Answer» B. fluid expansion system | |
Explanation: fluid expansion system is a method for measuring temperature, in which expansion of liquid is measured with temperature. |
146. |
IPTS stands for |
A. | international practical temperature scale |
B. | indian primary temperature scale |
C. | international primary temperature scale |
D. | international practical temperature standard |
Answer» A. international practical temperature scale | |
Explanation: ipts is the short form of name international standard temperature scale. |
147. |
In liquid in steel bulb thermometer, which liquid can be used for measuring temperature up to 60000C? |
A. | mercury |
B. | ether |
C. | water |
D. | none of the mentioned |
Answer» A. mercury | |
Explanation: mercury as a liquid provides temperature range of -4000c to 65000c. |
148. |
Which of the following is used as indication instrument in a liquid expansion system? |
A. | bellows |
B. | bourdon tube |
C. | ammeter |
D. | thermometer |
Answer» B. bourdon tube | |
Explanation: bourdon tube converts pressure into displacement and in liquid expansion systems output expansion pressure is applied to bourdon tube for indication. |
149. |
Which of the following is true for bimetallic type thermometer? |
A. | two metals have same temperature coefficients |
B. | two metals have different temperature coefficient |
C. | one metal is cooled always |
D. | none of the mentioned |
Answer» B. two metals have different temperature coefficient | |
Explanation: in a bimetallic type thermometer, two metals are used which are different in temperature coefficients. |
150. |
When bimetallic thermometer heated, curling occurs to the side of metal with least temperature coefficients. |
A. | true |
B. | false |
Answer» A. true | |
Explanation: a bimetallic type thermometer, when heated curls to the side of metal with least temperature coefficient. number of curls will be proportional to temperature applied. |
151. |
Analogous quantities of heat flow and temperature in electrical are and |
A. | potential and current |
B. | current and potential |
C. | power and potential |
D. | current and power |
Answer» B. current and potential | |
Explanation: heat flow in the thermal system is analogous to current flow in electrical, and temperature between two points is analogous to potential between two points in electrical. |
152. |
Ratio of net amount of heat received and stored in the body for certain time interval is known as |
A. | temperature |
B. | thermal coefficient |
C. | thermal storage capacity |
D. | none of the mentioned |
Answer» C. thermal storage capacity | |
Explanation: thermal storage capacity denoted by c is the ratio of the net amount of heat received and stored in the body. |
153. |
Heat transfer coefficient of a material with length l is |
A. | k/l |
B. | l/k |
C. | 1/k |
D. | kl |
Answer» A. k/l | |
Explanation: heat transfer coefficient of a material is the ratio of k and l, where k is the thermal conductivity of material and l is the length of the heat transfer path. |
154. |
Resistance temperature detector is |
A. | a electrical transducer |
B. | a mechanical transducer |
C. | a chemical transducer |
D. | a physical transducer |
Answer» A. a electrical transducer | |
Explanation: resistance temperature detector is an electrical transducer. it is used for measuring the variation in temperature. it is also known as a resistance thermometer. |
155. |
Sensing element in the thermometer must provide |
A. | small change in resistance |
B. | no change in resistance |
C. | large change in resistance |
D. | infinite change in resistance |
Answer» C. large change in resistance | |
Explanation: the sensing element in a thermometer must give a large change in the resistance for a given change in the temperature. |
156. |
Resistance thermometer provides the change in electrical resistance. |
A. | true |
B. | false |
Answer» A. true | |
Explanation: a resistance thermometer provides a change in the electrical resistance with respect to a variation in the temperature. basically resistance thermometers work on the principle of change in the electrical resistance with variation in the temperature. |
157. |
If the sensing element is large, then less amount of heat is required. |
A. | true |
B. | false |
Answer» B. false | |
Explanation: when the sensing element in a resistance thermometer is small in size, then less quantity of heat is required to raise the temperature. platinum, nickel and copper are the commonly used metals for measuring temperature. |
158. |
In a temperature sensing element |
A. | low value of α is required |
B. | infinite value of α is required |
C. | α must be zero |
D. | high value of α is required |
Answer» D. high value of α is required | |
Explanation: in order to achieve a large change in the value of resistance for a small change in the value of temperature, high value of α is required. change in resistance is measured through a wheatstone’s bridge. |
159. |
Nickel and its alloys can be used over a temperature range of |
A. | 100 to 450 k |
B. | 10 to 50 k |
C. | 0 to 25 k |
D. | 5 to 15 k |
Answer» A. 100 to 450 k | |
Explanation: temperature sensors constructed using nickel and its alloys can be used in the temperature range of 100 to 450 |
160. |
How can corrosion be prevented in a resistance thermometer? |
A. | by immersing the setup in oil |
B. | by enclosing the elements in a glass tube |
C. | by using guard rings |
D. | by painting the elements |
Answer» B. by enclosing the elements in a glass tube | |
Explanation: corrosion can be eliminated in a resistance thermometer by enclosing the elements in a protective tubular glass made of pyrex, quartz or crystal depending upon the temperature range. |
161. |
What is the maximum permissible error for class I micrometers? |
A. | 0.002 mm |
B. | 0.004 mm |
C. | 0.008 mm |
D. | 0.016 mm |
Answer» B. 0.004 mm |
162. |
Which of the following is caused by careless handling? |
A. | systematic error |
B. | gross error |
C. | random error |
D. | none of the mentioned |
Answer» B. gross error |
163. |
‘A system will be error free if we remove all systematic error’. |
A. | true |
B. | false |
Answer» B. false |
164. |
Which of the following is not a fundamental quantity? |
A. | length |
B. | angle |
C. | time |
D. | luminous intensity |
Answer» B. angle |
165. |
Which standard is fixed and used for industrial laboratories? |
A. | international standard |
B. | primary standard |
C. | secondary standard |
D. | working standard |
Answer» C. secondary standard |
166. |
Which of the following error is caused by poor calibration of the instrument? |
A. | random error |
B. | gross error |
C. | systematic error |
D. | precision error |
Answer» C. systematic error |
167. |
How systematic errors are eliminated? |
A. | frequent measurement |
B. | replacement of instrument |
C. | finding mean of reading |
D. | finding variance of reading |
Answer» B. replacement of instrument |
168. |
Starting position of an object is represented as x=5.1±0.2m and finishing position as y=6.9±0.3m. What will be the displacement and error in displacement? |
A. | displacement = 1m, error = 0.5m |
B. | displacement = 2m, error = 0.36m |
C. | displacement = 1.8m, error = 0.36m |
D. | displacement = 1.5m, error = 0.4m |
Answer» C. displacement = 1.8m, error = 0.36m |
169. |
Which of the following is correct for selective assembly? |
A. | not suitable for industrial purposes |
B. | cost increases due to automatic gauging |
C. | wastage is high due to selective selection |
D. | this method is followed in ball and roller bearing units |
Answer» D. this method is followed in ball and roller bearing units |
170. |
For checking straightness, straight edge is placed over a surface and these two are viewed against the light. Which of the following option true if colour of light is red? |
A. | gap between 0.12 to 0.17 mm |
B. | gap between 0.2 to 0.7 mm |
C. | gap between 1.7 to 2 mm |
D. | gap between 0.0012 to 0.0017 mm |
Answer» D. gap between 0.0012 to 0.0017 mm |
171. |
Which of the following is the best for the examination of surface finish? |
A. | touch inspection |
B. | visual inspection |
C. | scratch inspection |
D. | microscopic inspection |
Answer» D. microscopic inspection |
172. |
What is the relationship between Orificemeter diameter and pipe diameter |
A. | orificemeter diameter is 0.5 times the pipe diameter |
B. | orificemeter diameter is one third times the pipe diameter |
C. | orificemeter diameter is one fourth times the pipe diameter |
D. | orificemeter diameter is equal to the pipe diameter |
Answer» C. orificemeter diameter is one fourth times the pipe diameter |
173. |
3 TEMPERATURE: BIMETALLIC STRIP, THERMOCOUPLES |
A. | strain |
B. | pressure |
C. | displacement |
D. | voltage |
Answer» C. displacement |
174. |
Relation between temperature and resistance of a conductor is |
A. | rt = rref [1+t] |
B. | rt = rref [1+α∆t] |
C. | rt = rref [1-αt] |
D. | rt = rref [1-t] |
Answer» B. rt = rref [1+α∆t] |
175. |
Most metallic conductors have a |
A. | neutral temperature coefficient of resistance |
B. | negative temperature coefficient of resistance |
C. | positive temperature coefficient of resistance |
D. | zero temperature coefficient of resistance |
Answer» C. positive temperature coefficient of resistance |
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