There are various types of micrometers available in the market. Some of these are
Inside Micrometer
Outside micrometer
Dial Micrometer
Universal Micrometer
Tube micrometer
Screw thread micrometer
Disk micrometer
Depth micrometer
Height micrometer
Differential micrometer
2. The micrometer which is used to measure wire, sphere, shaft is
Inside micrometer
Outside micrometer
Tube Micrometer
Screw thread Micrometer
Answer.2. Outside Micrometer
Explanation:-
Outside Micrometer or External micrometer:- It is used for measuring outside diameters, widths, and thicknesses. It consists of a C-shaped frame with a stationary anvil and a movable spindle. The important parts of a micrometer are frame, anvil, spindle, locknut, thimble adjusting nut, sleeve, and ratchet stop.
It is used to measure circular section parts like outside diameter of shafts or length or thickness of small parts such as a wire.
3. Inside micrometer is used to measure ______
Bore or holes
Depth
Height
Surface area
Answer.1. Bore or Holes
Explanation:-
Inside micrometer:- It works on the same principle as that of the outside micrometer and is used for measuring large diameters say over 50 mm up to an accuracy of 0.01 mm by inserting extension rods of different lengths. The inside micrometer consists mainly of four parts:
Micrometer unit
Extension rod
Handle
Spacing collar
Inside Micrometers. Inside micrometers can be used to measure the inside diameter of a bore. To do this, place the tool inside the bore and extend the measuring surfaces until each end touches the bore’s surface. If the bore is large, it might be necessary to use an extension rod to increase the micrometer’s range. These extension rods come in various lengths. The inside micrometer is read in the same manner as an outside micrometer.
It is used for measuring bore diameters and slot widths from 50 millimeters to 210 millimeters. For anyone extension rod its measuring range is 20 millimeters. A range of extension rods in stepped lengths is provided in the case with the measuring head.
4. The range of accuracy of an inside micrometer is
0.05 mm
0.01 mm
0.1 mm
0.5 mm
Answer.2. 0.01 mm
Explanation:-
Inside micrometer works on the same principle as that of the outside micrometer and is used for measuring large diameters say over 50 mm up to an accuracy of 0.01 mm by inserting extension rods of different lengths.
5. Which of the following is/are limitations of the inside micrometer?
Inefficient below 50 mm of diameter
Hard to adjust
Both 1 and 2
None of the above
Answer.3. Both 1 and 2
Explanation:-
Inside diameter suffers from two important limitations.
(i) It cannot be used to measure small holes less than 50 millimeters in diameter.
(ii) It cannot be easily adjusted once it is in the hole and this affects the accuracy of contact “feel’ that can be obtained.
6. The range of external micrometer is limited to
50 mm
25 mm
10 mm
100 mm
Answer.2. 25 mm
Explanation:-
External Micrometer head limited to 25 mm range. Separate instruments required in steps of 25 mm or by using interchangeable anvils.
7. If the movable spindle is pointed in nature or in conical shape you are more likely using
Screw thread micrometer:- It is designed to measure the pitch diameter of screw threads to an accuracy of 0.01 mm. In construction, the screw thread micrometer, as shown in Fig. is similar to the outside micrometer with the following differences.
(1) The movable spindle is pointed or in a conical shape
(2) The end of the anvil is of the same form as the screw thread to be measured.
It measures pitch diameters directly. The anvil has an internal ‘vee’, which fits over the thread. Since the anvil is free to rotate, it can accommodate any rake range of thread. However, interchangeable anvils need to be used to cover a wide range of thread pitches.
8. Which of the following instrument is used to measure depths and groove spacing?
Tube micrometer
Depth Micrometer
Height micrometer
Disk micrometer
Answer.2. Depth micrometer
Explanation:-
Depth micrometers are used for measurements of depths, groove spacing, and groove widths.
The depth gauge micrometer is also based on the principle of the micrometer. It is similar in construction to an ordinary micrometer, but instead of a frame, it has a shoulder as shown in Fig. These micrometers also have an accuracy of 0.01 mm. A depth gauge micrometer is used for measuring the depth of holes in workshops.
9. In which of the following measuring instrument the scale is reversed as compared to a simple micrometer?
Tube micrometer
Height micrometer
Disk micrometer
Depth Micrometer
Answer.4. Depth Micrometer
Explanation:-
A depth micrometer is used for measuring the depth of holes and slots. You must take care when using a depth micrometer because its scales are reversed when compared with the familiar micrometer caliper. Also the measuring pressure tends to lift the micrometer off its seating.
The measuring range is 25 millimeters for any given rods. Typical rods give a range of 0 to 25 mm, 25 to 50 mm, 50 to 75 mm.
10. The disk micrometer is used to measure
Root tangent Length
Triangle Length
Parallel Length
Perpendicular length
Answer.1. Root tangent length
Explanation:-
Disk micrometer:- It is used for measuring the distance between two features with curvature i.e root tangent length. A tooth span micrometer is one such device that is used for measuring the span between the two teeth of a gear. Although it provides a convenient means for linear measurement, it is prone to error in measurement when the curvature of the feature does not closely match the curvature of the disk.
11. Which of the following micrometer is used for measuring the thickness of the pipe?
Disk micrometer
Depth micrometer
Tube micrometer
Screw thread micrometer
Answer.3. Tube micrometer
Explanation
Tube micrometers or ball contact micrometers are designed to measure the wall thickness of tubular parts, such as sleeves and collars. They also can be used for measuring from the inside of holes that are too small for the anvil end of a standard micrometer to be inserted.
12. Which of the following option is correct about the given statements about Digital micrometer?
Statement 1: Digital micrometer has an anvil, spindle, lock nut as Analog Micrometer Statement 2: It does not require a battery
Only statement 1 is true
Only statement 2 is true
Both the statements are true
Both the statements are false
Answer.1. Only statement 1 is true
Explanation:-
Digital Electronic Micrometers
A digital micrometer, like a customary micrometer, is used to measure the length, diameter, or thickness of an object.
Just as with a customary micrometer, an electronic digital micrometer has an anvil, spindle, lock nut, sleeve, thimble, and ratchet.
In addition, most digital micrometers have three buttons: ON/OFF or POWER, HOLD, and IN/mm. The micrometer has a fourth button: ZERO for resetting it to zero value.
Because the reading is electronically generated and digitally displayed on an LCD (liquid crystal display), a digital micrometer requires a battery. Digital micrometers come in various sizes.
13. Which of the following is/are advantages of Digital micrometer?
Data can be saved
Quick switching between different dimension
Data can be printed
All of the above
Answer.4. All of the above
Explanation
Advantages to digital micrometers:
(a) measurements are read in a single step on an LCD display.
(b) a button allows for switching between metric and inch measurements.
(c) some versions allow the data to be saved to a USB (universal serial bus) drive or printed.
(d) some versions are designed so that data can be sent wirelessly or with a traditional cable, and (e) can provide for SPC (statistical process control) analysis and documentation.
Note:- The one big disadvantage of an electronic digital micrometer is that it requires a battery. If the battery is dead, the micrometer will not operate. It is always a good idea to have a spare battery in your micrometer case.
14. What is the accuracy range of stick micrometers?
±0.005 mm
±0.05 mm
±0.5
±0.0005 mm
Answer.1. ±0.005 mm
Explanation
The accuracy of stick micrometers is of the order of ±0.005 mm. They are used to measure longer internal lengths. They have a series of extension rods to measure up to the maximum length.
15. The universal micrometer can be used as
Depth micrometer
Step Micrometer
Outside micrometer
All of the above
Answer.4. All of the above
Explanation:-
Universal micrometer:- It has interchangeable anvils such as flat, spherical, spline, disk, or knife edge. It is called universal because of its modular design. The micrometer fitted with the required accessories can function as an outside micrometer, a depth micrometer, a step micrometer, etc.
