

MCQOPTIONS
Saved Bookmarks
This section includes 382 Mcqs, each offering curated multiple-choice questions to sharpen your Mechanical Engineering knowledge and support exam preparation. Choose a topic below to get started.
251. |
In Magnetic abrasive finishing, which of the following particles do not contribute to the material removal? |
A. | abrasive particles |
B. | magnetic particles |
C. | non-magnetic particles |
D. | all of the mentioned |
Answer» D. all of the mentioned | |
252. |
Which of the following type of tools, are required for magnetic field assisted polishing? |
A. | rigid tools |
B. | expensive tools |
C. | magnetic tools |
D. | ultra precession tools |
Answer» D. ultra precession tools | |
253. |
Pumping of electrolyte through the narrow gaps causes, which type of forces on tool and work piece? |
A. | large |
B. | small |
C. | negligible |
D. | no force |
Answer» B. small | |
254. |
Electro chemical machining process cannot produce which of the following mentioned below? |
A. | drilled holes |
B. | deburred edges |
C. | sharp edges |
D. | all of the mentioned |
Answer» D. all of the mentioned | |
255. |
State whether the following statement is true or false regarding the limitations of ECM. “In electrochemical machining, duplicating the tool is easier.†|
A. | true |
B. | false |
Answer» C. | |
256. |
How are material removal rates of ECM, when compared to that of conventional methods? |
A. | slower |
B. | faster |
C. | same |
D. | none of the mentioned |
Answer» B. faster | |
257. |
How much amount of energy is consumed in Electro chemical machining? |
A. | very small |
B. | small |
C. | medium |
D. | large |
Answer» E. | |
258. |
Which of the following are the limitations of electro chemical machining? |
A. | removal of hydrogen |
B. | handling the electrolyte |
C. | energy consumption |
D. | all of the mentioned |
Answer» E. | |
259. |
What are the requirements of labour for machining purpose in Electrochemical machining? |
A. | low |
B. | medium |
C. | high |
D. | very high |
Answer» B. medium | |
260. |
Which of the following materials can be machined using ECM? |
A. | hard nonconductive materials |
B. | hard conductive materials |
C. | all nonconductive materials |
D. | none of the mentioned |
Answer» C. all nonconductive materials | |
261. |
Compared to other processes, machining is done at                      voltages for high rates of material removal. |
A. | low |
B. | medium |
C. | high |
D. | very low |
Answer» D. very low | |
262. |
Passivation is done on electrolytes in order to form which of the following? |
A. | passive layer on machined parts |
B. | passive layer on cathode |
C. | passive layer on machined parts & cathode |
D. | none of the mentioned |
Answer» B. passive layer on cathode | |
263. |
130 mm. |
A. | ± 0.01 mm |
B. | ± 0.025 mm |
C. | ± 0.13 mm |
D. | ± 0.25 mm |
Answer» E. | |
264. |
Fine dimensional control can be obtained if throwing power of electrolyte is |
A. | low |
B. | medium |
C. | high |
D. | very high |
Answer» B. medium | |
265. |
What happens when the current density is low in ECM? |
A. | pitting occurs |
B. | etching occurs |
C. | pitting & etching occurs |
D. | none of the mentioned |
Answer» D. none of the mentioned | |
266. |
If there is an increase in the electrolyte flow, what happens to the rate of film formation? |
A. | increases |
B. | decreases |
C. | remains same |
D. | all of the mentioned |
Answer» C. remains same | |
267. |
For high process accuracy, which of the following factors are needed? |
A. | high feed rate |
B. | high conductivity |
C. | high feed rate & high conductivity |
D. | none of the mentioned |
Answer» D. none of the mentioned | |
268. |
If the current density is high as required, what type of machining occurs? |
A. | pitting |
B. | polishing |
C. | etching |
D. | all of the mentioned |
Answer» C. etching | |
269. |
Tool insulation that                      the side machining action is needed in the process of ECM. |
A. | limits |
B. | enhances |
C. | maintains |
D. | none of the mentioned |
Answer» B. enhances | |
270. |
Which properties of electrolyte does not affect the accuracy of the process? |
A. | temperature |
B. | concentration |
C. | non-reactive |
D. | pressure |
Answer» D. pressure | |
271. |
Accuracy of machining is affected by, which of the following factors? |
A. | material |
B. | gap voltage |
C. | feed rate |
D. | all of the mentioned |
Answer» E. | |
272. |
Which type of gap width is necessary for a higher degree of accuracy? |
A. | very small |
B. | small |
C. | medium |
D. | high |
Answer» C. medium | |
273. |
In Electrochemical machining, larger grain size causes which type of finish? |
A. | smoother |
B. | rougher |
C. | finer |
D. | all of the mentioned |
Answer» C. finer | |
274. |
Between which values does the side gap’s surface roughness vary? |
A. | >1 µm |
B. | >3 µm |
C. | >5 µm |
D. | >7 µm |
Answer» D. >7 µm | |
275. |
For a better surface finish, which type of current distribution is required? |
A. | even |
B. | uneven |
C. | even & uneven |
D. | none of the mentioned |
Answer» B. uneven | |
276. |
Surface roughness depend on which of the following quantities? |
A. | crystallographic irregularities |
B. | alloy composition |
C. | distribution of current density |
D. | all of the mentioned |
Answer» E. | |
277. |
What must be the working voltage in Electrochemical machining? |
A. | 10 v |
B. | 20 v |
C. | 30 v |
D. | 40 v |
Answer» C. 30 v | |
278. |
When machining Ti, in Nacl electrolyte, what values of current efficiencies are obtained? |
A. | 10 – 20 % |
B. | 20 – 30 % |
C. | 30 – 50 % |
D. | 50 – 80 % |
Answer» B. 20 – 30 % | |
279. |
State whether the following statement is true or false about electrolyte in ECM. “Machinability in ECM is enhanced, when electrolyte is heated.†|
A. | true |
B. | false |
Answer» B. false | |
280. |
When the electrolyte flow is low, what happens to the current efficiency? |
A. | increases |
B. | decreases |
C. | remains same |
D. | increase and then decrease |
Answer» C. remains same | |
281. |
For alloys, which type of electrolyte is used in ECM? |
A. | single component |
B. | double component |
C. | multi component |
D. | triple component |
Answer» D. triple component | |
282. |
Nickel can be machined with 100% current efficiency, when current density value is |
A. | 10 a/cm2 |
B. | 25 a/cm2 |
C. | 45 a/cm2 |
D. | 80 a/cm2 |
Answer» C. 45 a/cm2 | |
283. |
Better surface finish and higher accuracy depend on which of the factors below? |
A. | chemical composition of the electrolyte |
B. | current density |
C. | all of the mentioned |
D. | none of the mentioned |
Answer» D. none of the mentioned | |
284. |
Electro chemical dissolution phase starts with the movement of ions between which two components? |
A. | cathode and anode |
B. | cathode and power source |
C. | power source and anode |
D. | power source and electrolyte |
Answer» B. cathode and power source | |
285. |
Too small gap causes which of the following effects? |
A. | sparking |
B. | short circuit |
C. | sparking & short circuit |
D. | none of the mentioned |
Answer» D. none of the mentioned | |
286. |
If the gap thickness is greater than equilibrium thickness what will be MRR? |
A. | mrr is less than feed rate |
B. | mrr is greater than feed rate |
C. | mrr is equal to feed rate |
D. | none of the mentioned |
Answer» B. mrr is greater than feed rate | |
287. |
At constant gap thickness material removal becomes equal to feed rate. What is this gap called? |
A. | equal gap |
B. | equilibrium gap |
C. | unique gap |
D. | narrow gap |
Answer» C. unique gap | |
288. |
When local metal removal rates are high, how will be the current density and current efficiency? |
A. | high |
B. | medium |
C. | low |
D. | very low |
Answer» B. medium | |
289. |
During ECM drilling, decrease in feed rates lead to which type of machining gaps? |
A. | wider |
B. | narrow |
C. | small |
D. | none of the mentioned |
Answer» B. narrow | |
290. |
In ECM, gap increase proportional to which relation of time below? |
A. | square of time |
B. | square root of time |
C. | cube of time |
D. | cube root of time |
Answer» C. cube of time | |
291. |
At constant feed rates what happens to gap thickness? |
A. | increases |
B. | decreases |
C. | becomes constant |
D. | none of the mentioned |
Answer» D. none of the mentioned | |
292. |
State whether the following statement is true or false regarding the working principles. “In ECM, grain boundary attacks remove the grains through electrolytic forces.†|
A. | true |
B. | false |
Answer» B. false | |
293. |
Apparent current efficiency is due to which of the following factors? |
A. | choice of wrong valence |
B. | passivation of anodic surface |
C. | gas evolution at anode |
D. | all of the mentioned |
Answer» E. | |
294. |
In the following ratios of metal dissolved amounts, which one represent the current efficiency? |
A. | observed to theoretical |
B. | theoretical to observed |
C. | all of the mentioned |
D. | none of the mentioned |
Answer» B. theoretical to observed | |
295. |
Current efficiency depends on which of the following in ECM? |
A. | anodic material |
B. | electrolyte |
C. | anodic material & electrolyte |
D. | none of the mentioned |
Answer» D. none of the mentioned | |
296. |
What must be the value of velocity of the electrolytic solution? |
A. | 10 to 15 m/s |
B. | 25 to 50 m/s |
C. | 60 to 100 m/s |
D. | 120 to 200 m/s |
Answer» C. 60 to 100 m/s | |
297. |
Local metal removal rates are high at which gap locations mentioned below? |
A. | small gap |
B. | medium gap |
C. | large gap |
D. | none of the mentioned |
Answer» B. medium gap | |
298. |
What must be the value of the pressure of electrolytic solution used in ECM? |
A. | 1 to 10 kpa |
B. | 10 to 80 kpa |
C. | 100 to 200 kpa |
D. | 300 to 400 kpa |
Answer» D. 300 to 400 kpa | |
299. |
What must be the value of electrolytic temperature in ECM? |
A. | 2 to 14oc |
B. | 22 to 45oc |
C. | 46 to 57oc |
D. | 62 to 76oc |
Answer» C. 46 to 57oc | |
300. |
Selection of electrolyte does not depend on which of the following factors? |
A. | work piece material |
B. | dimensional tolerance |
C. | heat affected zones |
D. | machining productivity |
Answer» D. machining productivity | |