What is the difference between moment and torque is the question that pops up in most of our minds?
In physics, they signify the same thing but in mechanics, they hold slightly different meanings. Both have the same unit i.e. N-m but torque is a movement force whereas the moment Is a static force. Torque is used where there is rotation involved whereas moment Is used where there is no rotation.
Application of moment and torque for varied and interesting to observe. I hope everyone has played on a seesaw at least once in their life. What if I tell you that you can keep the saw balanced by having a 120 kg person one side and a 50kg person on the other side?
It seems difficult to accept but if you place them in such a way that the lighter person is at 3m from the center and the healthy person is at 1m. They both will apply the same moment and the seesaw will be balanced.
In rural areas, people still use the concept of the moment to churn milk. By providing a torque to the handle with the help of the rope the wooden stick rotates about its axis and thus, in turn, churns the milk.
A similar concept of torque is used in old dams where the force of the falling water rotated the water wheel. The water wheel was connected to a dynamo thus generating electricity by the principle of conversion of kinetic energy into potential energy.
The International System of Units (SI)has become the fundamental basis of scientific measurement worldwide. This system is an extension and refinement of the metric system, which is more superior and convenient than other systems. It provides one basic unit for each physical quantity. So, the 7 units of measurement are follow
The basic fundamental unit of mass is “Kg”. We also measure mass in Gram, Pound, Metric ton, Stone, Microgram, Carat, etc.
The basic fundamental unit of Time is “Sec(s)”. We also express time in seconds, minutes, hours, days, weeks, years, etc
3. Electric Current –
The basic fundamental unit of Electric Current is “Ampere(A)”.
4. Amount of Substance –
The amount of Substance is a dimensionless expression of the number of particles in a particle or object. The basic fundamental unit of Amount of Substance is “Mole”. The amount of substance all called material quantity.
The SI unit of Illumination is “Candela”. Candela is denoted by symbol ‘cd’. Some other units are lux, lumen, etc.
The SI unit of Distance is “Meter”. Distance also measures in mm, cm, km, yard, inch, foot, feet, etc.
The SI unit of temperature is “kelvin”, expressed as the word “K”.Temperature 0 K is known as “absolute zero.”
We use two types of scale in measuring temperature that is –
1.Relative scales [Fahrenheit (°F) and Celsius (°C)]
This seven basic quality tools, which can assist an organization for problem solving and process improvements. Learn this awesome skill Free Here.
Video of Seven QC tools
The first who introduce the seven basic tools is Dr. Kaoru Ishikawa (1968).
Check sheets are sheets that are designed in advance to collect the necessary data easily and systematically, which allows the efficient checking off all items for inspection and verification.
Check sheets are tools for collecting data. They are designed specifically for the type of data to be collected. Check sheets aid in the systematic collection of data.
Some examples of check sheets are daily maintenance check sheets,
attendance records, production log books, etc
The histogram is a very useful tool to describe a sense of the frequency distribution of observed values of a variable.
Histograms or Frequency Distribution Diagrams are bar charts showing the distribution pattern of observations grouped inconvenient class intervals and arranged in order of magnitude.
It should be designed properly for those working into the operation
the process can easily utilize and understand them.
Pareto Analysis introduced by an Italian economist Vilfredo Pareto,
who worked with income and other unequal distributions in the 19th century,
he noticed that 80% of the wealth was owned by only 20% of the
population. Which means the majority of defects are caused by a few defective items later, the Pareto principle was developed by Juran in 1950.
Kaoru Ishikawa is considered by many researchers to be the founder and the first promoter of the ‘Fishbone’ diagram (or Cause-and-Effect Diagram) for root cause analysis and the concept of Quality Control (QC) circles.
A Cause-and-Effect Diagram is a tool that shows a systematic relationship
between a result or a symptom of an effect and its possible causes.
When solving a problem or analyzing a situation one needs to know the relationship between two variables.
Scatter diagram is a powerful tool to draw the distribution of information
in two dimensions, which helps to detect and analyze a pattern
relationships between two quality and compliance variables (as an
independent variable and a dependent variable), an understanding if there is a relationship between them, so what kind of relationship is (Weak or strong and positive or negative).
A Flowchart visualizes a picture including the inputs, activities, decision points, and outputs for using and understanding easily concerning the overall objective through the process.
Control chart or Shewhart control chart was introduced and developed by Walter A. Shewhart in the 1920s at the Bell Telephone Laboratories and is likely the most “technically sophisticated” for quality management (Montgomery, 2009).
Control charts are a special form of “run chart that illustrates the amount and nature of variation in the process over time”.
Also, it can draw and describe what has been happening in the process.
As a student, a question popped in my mind as soon as I heard about Numerical Analysis. What is so special about this field of mathematics and how is it different?
In the search for my answer to this question, I explored Numerical Analysis. To put it simply numerical analysis is used to help us find solutions to lengthy problems in general or statistically indeterminant problems (i.e. where the number of variables is more than the number of equations available).
If this is such a powerful tool, then why do we need to remember lengthy equations to find the roots of equations, to begin with?
Numerical analysis even though a powerful tool has its downsides, as you always get an approximation and not the exact answer. The error in results can be reduced to a significant amount depending upon our needs.
Thus, if you’re designing a system for nuclear power plant you need a very high level of accuracy and if you’re designing a system for a college project you may need significantly lesser accuracy.
As for importance take the example of weather predictions.
Have you ever wondered how do they calculate how the weather is going to be like in the future? The advanced numerical analysis provides you the solution with approximate but accurate results.
You know that it takes time to solve an order 3 equation and there are limited ways in which you can solve it. What if I say that you’ve to solve a 100-order equation? Which is not possible to solve using the analytical method?
You’re working in a manufacturing plant and you want to predict the sales based upon the trend that has been followed in the past and if there is a lot of variation then it gets tedious to do it manually.
There is software such as MATLAB or Octave where you can code that calculates the solution to these and many other complicated problems.
Vernier Caliper is a widely used linear measurement instrument with a least count of 0.02 mm. It is used to measure linear dimensions like length, diameter, depth.
It is Basic Instrument of measurement, consist of two types of scale
The main scale and the Vernier scale that can slide along the main scale. Two types of measurement we can do, the first one is through the external jaw (measure external dimensions) and another one is internal jaw (measure internal dimensions).
02. Outside Micrometer
External Micrometer is also known as Outside Micrometer or External Micrometer.
It is used to check outside diameter of circle by the means of accuracy of 0.01 mm or up to 0.001 mm.
Vernier type Micrometer gives highest acceptable accuracy of 1 micron such gauge is vernier type micrometer.
03. Vernier Height Gauge
Vernier height gauge used to measure vertical dimension from
reference ground. Vernier Height Gauge consist of a graduated scale or
bar is held in a vertical position by a finely ground fixed base.
The graduated scale has least count of 0.02 mm like Vernier Caliper
has. And the way of taking a reading of measurement in Vernier Height
Gauge is same as in Vernier gauge.
04. Steel Scale
Steel scale is single piece linear measuring instrument.
Steel scale indicates two units that are cm and inches, cm division on one side and inches, on another side.
05. Vernier Depth Gauge
Vernier Depth Gauge as the name suggests is used to measure the depth from the surface of reference of an object.
Vernier caliper also has depth bar but this can not be used as the standard measurement.
06. Vernier Bevel Protractor
A simple protractor is a basic device used for measuring angles with a
least count of 1° or ½°. Bevel Protractor is an angular measuring
instrument capable of measuring angles with a least count of 5’.
The protractor dial is graduated in degrees with every tenth degree numbered. The sliding blade is fitted into this dial I.e. it may be extended to either direction and set at an angle to the base.
07. Plunger Dial Gauge
The dial indicator or the Plunger dial gauge is one of the simplest and the most widely used mechanical comparator.
First of all the use of plunger dial gauge used to compare work-pieces against a master
08. Lever Dial Gauge
Lever Dial Gauge also knew as Test Indicator. It used to measure sensitive contact.
Lever Dial gauge usually measure up to 0.80 mm. But some special type lever dial design for measurement up to 2 mm.
09. Engineering Square
A ruler can be used to draw straight lines but there is no quarranty
that the line drawn is accurate and exactly straight,this is where the
engineering square is brought into use.
An engineering square also known as machinist square is similar in size and construction to a try square.
It is a tool used for making straight lines and are used to measure angles.
10. V Block
In Industries where precise marking and firm holding of objects is
required, V-Blocks play a major role and are extremely important
The construction had two clamps:screw clamp and a U shaped handle like clamp and a V-block .
11. Radius Gauge
Gauges are derived from the French word”jauge” which means the result
of the measurement. We are all aware that gauges are used to measure
the thickness, size or capacity of something.
Likewise, radius gauges are instruments that are used to measure the radius of the object.
The radius gauge is combined with another gauge known as fillet gauge which in mechanics means a rounding of the part design.
12. Digital Vernier Caliper
Digital Vernier Caliper is upgrading version of Analog Vernier Caliper, which is a widely used linear measurement instrument with a least count of 0.01 mm, more accurate than Analog.
This Digital type of vernier is similar to Analog Vernier Caliper
Instead Dimension output in Digital Manner that is more convinces than
It also consists of two types of scale –
The main scale and the Digital display that can slide along the main scale. Two types of measurement we can do, the first one is through external jaw (that measure external dimensions like shaft) and another one is internal jaw (measure internal dimensions like hole).
13. Digital Micrometer
Digital Micrometer is a very popular instrument these days because of its easy of compactness of taking an observation.
Digital Micrometer can observe measurement in mm or inch depend upon our need basis.
14. Inside Micrometer
Inside Micrometer is used to measure the larger internal dimension. Inside Micrometer can measure the internal Diameter of holes and registers.
Types of Micrometer
There are various types of micrometers available in the industry each
used for a specific purpose. One such micrometer is the “Inside
The inside micrometer is used to measure the inner diameter of
objects that are bonded by walls,cylindrical bore or hollow pipe.There
are two types of Inside Micrometer
Analog type Inside Micrometer
Digital type Inside Micrometer
15. Depth Micrometer
We also measure depth through Vernier caliper, but Vernier caliper
does not deliver as much as accuracy and precision, because extension
rod of Vernier caliper has no standard, it used only for comparison
Depth micrometer used to measure the depth of an object with precision and accuracy with least count of 0.01 mm. The measuring span is 25 mm just like in micrometer, that can change by changing upsetting rod.
16. Measuring Tape
Measuring tape is used to measuring long distance.
17. Digital Height Gauge
The electronic Height gauge is very compact, simple, easy to use
instrument widely used in industries, tool rooms, workshops etc.
Some think you should consider while handling Electronic Height Gauge, Because of the cost of Electronic Height gauge matter in any industries or organization.
18. Electronic Height Gauge
Electronic height gauge is advance form of height gauge. It has higher accuracy and multi function.
An Electronic height gauge can measure diameter,angle, parallelism, squareness along with length.
19. Digital Universal Caliper
Digital universal caliper is widely used for measure inner and outer length of work-piece
20. Sine Bar
Sine bar is a precision angle measuring instrument along with slip gauges. The name suggests that Sine bar work on sine principle. Slip gauge used to build up the height of sine bar.
The required angle is obtained when the difference in height between the two rollers is equal to the Sine of the angle multiplied by the distance between the centers of the rollers.
21. Digital Protractor
Digital Protractor measure an angle over 360 degree with a high accuracy of 0.1 degree. Digital Protractor is very simple and ease to measure angle by just putting between levels or surface.
22. Spirit level
To check level of any surface or table, spirit level is used for leveling.
23. Slip Gauge Set
Slip Gauge is set standard size rectangular shape block. Slip gauges are available in standard sets in both metric and inch units.
In metric units, sets of 31, 48, 56, and 103 pieces are available.
For example, the set of 103 pieces consists of the following:
One piece of 1.005 mm
49 pieces ranging from 1.01 to 1.49 mm in steps of 0.01 mm
49 pieces ranging from 0.5 to 24.5 mm in steps of 0.5 mm
Four pieces ranging from 25 to 100 mm in steps of 25 mm
24. Bore Dial Gauge
Bore Dial Gauge use to measure the inner diameter of the hole, it is gauge fitted with a plunger dial gauge. In this video, you are able to know how to measure diameter with a bore dial gauge.
Bore dial gauge used within the standard range that means bore dial gauge have a standard set of pins(anvils) with the variable range of up to 2 mm.
25. Feeler Gauge
A Feeler gauge is used to measure the clearance between two parallel
flat faces for example piston and cylinder. As the name suggests, feeler
gauge called as to measure neither tide nor freely.
Feeler gauges are used for measurement of clearances.
It is a tool that measures air or narrow gap widths between two surfaces in engines and machinery.
Feeler gauge available in no. of the blade like 10,13,20 and 28. With a step of 0.05 and 0.10 mm.
Thermocouple consist of two dissimilar conductor wire, made from different metals. These wire are welded together at one end, form a junction used to measure temperature.
Thermistors have a high coefficient of resistivity. Thermistors are made of semiconductor of solid type.
The suitable temperature measuring range for thermistor is -100 degree Celsius to 300 degree Celsius. Some special type thermistor can measure up to 600 degree of temperature.
The change in temperature is measured by changes in its resistance. So, the Wheatstone bridge circuit is used for it.
Also, thermistor can convert changes in temperature to corresponding changes in voltage as a current.
Air gets pulled down by gravity and hence air exerts pressure on
objects. One such example of measurement is known as a barometer.
Barometers are scientific instruments that are used for the
measurement of atmospheric or air pressure. It is an important and
essential tool used in the meteorological department for forecasting
short term weather and altitude changes.
The barometers should be kept at the same level and cannot measure air pressure above the altitude of 5,000 feet. Initially, water-based barometers were used, later it was replaced by mercury and aneroid barometers which the two most commonly used barometers.
29. Snap gauge
Snap gauge is GO and NOGO type gauge. That means snap gauge consist 2 fixed measured distance or gap, one is known as GO and another one is known as NOGO.
30. Plain Plug gauge
Plug gauge is used for assessment of hole or diameter of an object. With specified tolerance of GO and NOGO side, plug gauge is also known as pin gauge.
Behalf of checking the diameter plug gauge also use in comparing, setting, calibrating of other gauges.
In an electric circuit, even if the switch or loop is closed, it is difficult to know whether the current is flowing, hence for this purpose galvanometer was introduced in the circuit.