1.Define force.
Force may be defined as a cause that produces resistance or obstruction to any
moving body or change the motion of a body.
2. Define speed.
Speed is a variable which refers to the revolutions per minute of some piece of
rotating equipment.
3. Which is the most frequently used speed measuring instrument?
Tachometer
4. What are the types of tachometer?
a) A.C. tacho generator
b) D.C. tacho generator
5. What are the types of D.C.tacho generator?
a) Permanent magnet type
b) Separately excited field type
6. What are the disadvantages of D.C. tacho generator?
A.C. ripple is present in the output signal.
The magnitude of the ripple is 2% of
the outPut D.C.level.
7. Name the types of rotor used in A.C.tacho generators.
a) Drag cup rotor
b) Squirrel cage rotor
8.What are the advantages of Squirrel cage rotor?
*Cheaper
*Occupies less space
9. Give some applications of drag cup tacho generator.
It is commonly used in the speedometers of motor vehicles and as a speed
indicator for aeroengines.
10. Give the formula to calculate the shaft speed.
Shaft speed = (disk speed * No. of openings in the disk) / No.of images
11. Define torque.
Torque is defined as the force which tends to change the linear motion or rotation
of a body.
12. What is the other name for inline stationary torque sensor?
Relative regular twist torque sensor
13. What are the types of torque transducer?
i) Inline rotating torque sensor
ii) Inline stationary torque sensor
iii) Optical torque sensor
iv) Proximity torque sensor
14. Write the relationship between torque and force.
T = F . D
where T -> Torque
F -> Force
D -> Perpenticular distance between the axis of rotation of the line of
action of the force
15. What are the advantages of optical torque sensor?
Low cost, small physical size
16. Write the formula for determining the actual speed in a stroboscope.
Actual speed ,fr =fl fn (n-1) / ( fn - fl )
fn is the highest flashing speed
fl is the lowest flashing speed
n is the no. of flashing frequencies
17. Define load cell.
Load cell are devices that convert force into pressure , which are then measured.
18. Write down the range, accuracy and resolution in hydrostatic or hydraulic load cell.
Range of force measurement = 0 to 30000 N
Accuracy = 0.1%
Resolution = 0.02%
19. Why magneto elastic load cell is also called pressductor load cell?
The degree of change has a direct relationship with the applied stress or force. So
it is called pressductor load cell.
20. What are the advantages of magneto elastic load cell?
• Extremely robust transducer
• Produces relatively high output signal levels
• Overload ratings are as high as 15 times the rated loads
1. What are the advantages of using Baume sclae?
It is used for liquids both higher and heavier than water.
2. Write the abbreviation of API scale.
API - American Petroleum Institute
3. Write the disadvantages of bridge type gas densitometer.
The major disadvantage is that the variations in ambient temperature will
introduce errors.
4. Write the formula for determining the height in a pressure head type densitometer.
H = Span / Specific gravity maximum - Specific gravity minimum
5. Give some of the materials which are used for the manufacturing of a float.
Pyrex, Plastic
6. For what purpose accelerometers are used?
• For the measurement of shock & vibration
• For gross measurement of acceleration of vehicles like aircraft,
submarines etc.
7. What are the advantages of LVDT?
• It is used for steady state and low freequency vibration measurements.
• Smaller mass, so, it is used for the measurement of vibrations of higher
frequencies.
(ii) Good accuracy
(iii) More stable
(iv) Fast speed response
(v) Simple to maintain
3) What are the disadvantages of strain gauge pressure transducer?
(i) High cost
(ii) Requires constant voltage supply.
(iii) Electrical readout is necessary.
(iv) Temperature compensation is required.
4) What is the principle of operation of a piezoelectric pressure transducer?
When pressure is applied to a piezoelectric crystal such as quartz, an
electrical charge is generated.
5) What are the types of thermal conductivity gauges?
(a) Pirani gauge
(b) Thermocouple gauge
6) What is the purpose of ionization gauge?
Ionization gauge is used to measure the density of a gas.
7) Write down the formula for calculating the pressure in a Mcleod gauge?
P = KHHo(1- KH)
K->Constant
H-> Difference in heights of the two mercury columns.
Ho->Height of the top of the closed capillary tube above the line marked on
the tube.
8) What is the function of a dead weight tester?
Dead weight tester is used to calibrate bourdon gauges .It is used as a measuring
device and also as a calibration method.
9) What are the disadvantages of using thermocouple gauge?
(i) Easily damaged by organic vapours
(ii) The filaments can be coated with a deposit of devapourised vapours
which alters the way the filament transfers heat.
10) Define thermal conductivity
The ability of the material to carry heat by conduction is called as the
thermal conductivity.
11) What are the materials used in the construction of piezoelectric pressure transducer?
These devices use piezoelectric characteristic of crystalline and ceramic
materials such as quartz.
12) What are the main parts in electrical pressure transducer?
(i)Pressure sensing element such as a bellow, a diaphragm or a bourdon tube.
(ii)Primary conversion element
(iii)Secondary conversion element.
13) What are the advantages of capacitive pressure transducer?
• It gives rapid response to changes in pressure
• It can withstand a lot of vibration
• It has a good frequency response and can measure both static &
dynamic changes.
14) What is a vacuum pressure?
Force may be defined as a cause that produces resistance or obstruction to any
moving body or change the motion of a body.
2. Define speed.
Speed is a variable which refers to the revolutions per minute of some piece of
rotating equipment.
3. Which is the most frequently used speed measuring instrument?
Tachometer
4. What are the types of tachometer?
a) A.C. tacho generator
b) D.C. tacho generator
5. What are the types of D.C.tacho generator?
a) Permanent magnet type
b) Separately excited field type
6. What are the disadvantages of D.C. tacho generator?
A.C. ripple is present in the output signal.
The magnitude of the ripple is 2% of
the outPut D.C.level.
7. Name the types of rotor used in A.C.tacho generators.
a) Drag cup rotor
b) Squirrel cage rotor
8.What are the advantages of Squirrel cage rotor?
*Cheaper
*Occupies less space
9. Give some applications of drag cup tacho generator.
It is commonly used in the speedometers of motor vehicles and as a speed
indicator for aeroengines.
10. Give the formula to calculate the shaft speed.
Shaft speed = (disk speed * No. of openings in the disk) / No.of images
11. Define torque.
Torque is defined as the force which tends to change the linear motion or rotation
of a body.
12. What is the other name for inline stationary torque sensor?
Relative regular twist torque sensor
13. What are the types of torque transducer?
i) Inline rotating torque sensor
ii) Inline stationary torque sensor
iii) Optical torque sensor
iv) Proximity torque sensor
14. Write the relationship between torque and force.
T = F . D
where T -> Torque
F -> Force
D -> Perpenticular distance between the axis of rotation of the line of
action of the force
15. What are the advantages of optical torque sensor?
Low cost, small physical size
16. Write the formula for determining the actual speed in a stroboscope.
Actual speed ,fr =fl fn (n-1) / ( fn - fl )
fn is the highest flashing speed
fl is the lowest flashing speed
n is the no. of flashing frequencies
17. Define load cell.
Load cell are devices that convert force into pressure , which are then measured.
18. Write down the range, accuracy and resolution in hydrostatic or hydraulic load cell.
Range of force measurement = 0 to 30000 N
Accuracy = 0.1%
Resolution = 0.02%
19. Why magneto elastic load cell is also called pressductor load cell?
The degree of change has a direct relationship with the applied stress or force. So
it is called pressductor load cell.
20. What are the advantages of magneto elastic load cell?
• Extremely robust transducer
• Produces relatively high output signal levels
• Overload ratings are as high as 15 times the rated loads
1. What are the advantages of using Baume sclae?
It is used for liquids both higher and heavier than water.
2. Write the abbreviation of API scale.
API - American Petroleum Institute
3. Write the disadvantages of bridge type gas densitometer.
The major disadvantage is that the variations in ambient temperature will
introduce errors.
4. Write the formula for determining the height in a pressure head type densitometer.
H = Span / Specific gravity maximum - Specific gravity minimum
5. Give some of the materials which are used for the manufacturing of a float.
Pyrex, Plastic
6. For what purpose accelerometers are used?
• For the measurement of shock & vibration
• For gross measurement of acceleration of vehicles like aircraft,
submarines etc.
7. What are the advantages of LVDT?
• It is used for steady state and low freequency vibration measurements.
• Smaller mass, so, it is used for the measurement of vibrations of higher
frequencies.
(ii) Good accuracy
(iii) More stable
(iv) Fast speed response
(v) Simple to maintain
3) What are the disadvantages of strain gauge pressure transducer?
(i) High cost
(ii) Requires constant voltage supply.
(iii) Electrical readout is necessary.
(iv) Temperature compensation is required.
4) What is the principle of operation of a piezoelectric pressure transducer?
When pressure is applied to a piezoelectric crystal such as quartz, an
electrical charge is generated.
5) What are the types of thermal conductivity gauges?
(a) Pirani gauge
(b) Thermocouple gauge
6) What is the purpose of ionization gauge?
Ionization gauge is used to measure the density of a gas.
7) Write down the formula for calculating the pressure in a Mcleod gauge?
P = KHHo(1- KH)
K->Constant
H-> Difference in heights of the two mercury columns.
Ho->Height of the top of the closed capillary tube above the line marked on
the tube.
8) What is the function of a dead weight tester?
Dead weight tester is used to calibrate bourdon gauges .It is used as a measuring
device and also as a calibration method.
9) What are the disadvantages of using thermocouple gauge?
(i) Easily damaged by organic vapours
(ii) The filaments can be coated with a deposit of devapourised vapours
which alters the way the filament transfers heat.
10) Define thermal conductivity
The ability of the material to carry heat by conduction is called as the
thermal conductivity.
11) What are the materials used in the construction of piezoelectric pressure transducer?
These devices use piezoelectric characteristic of crystalline and ceramic
materials such as quartz.
12) What are the main parts in electrical pressure transducer?
(i)Pressure sensing element such as a bellow, a diaphragm or a bourdon tube.
(ii)Primary conversion element
(iii)Secondary conversion element.
13) What are the advantages of capacitive pressure transducer?
• It gives rapid response to changes in pressure
• It can withstand a lot of vibration
• It has a good frequency response and can measure both static &
dynamic changes.
14) What is a vacuum pressure?
Hello,
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