Metrology-1-Intro

Question 1

What is Metrology?

Answer 1

Metrology is the science of MEASUREMENT & CALIBRATION

Question 2

Without Measurements there can be no?

Answer 2

fitness for purpose or
conformity/compliance to design specifications

Question 3

Without calibration there can be no?

Answer 3

national international
measurement conformity, or measurement confidence

Question 4

For Manufacturing companies compliance with what standards is necessary?

Answer 4

ISO 9000 and
ISO/DIS 14253

Question 5

Metrology allows what comparison?

Answer 5

comparison of the manufactured article with
the original specification

Question 6

Metrology helps improve what?

Answer 6

product quality, reduce defects
and reduce scrap rates, hence increasing market share,
competitiveness, survivability and profitability

Question 7

4 commonly used systems of units?

Answer 7

• British Imperial system
• Centimetre-Gram-Second (CGS/cgs) system
• Metre-Kilogram-Second (MKS/mks) system
• Systeme International d’Unites (SI)

Question 8

What is he legal measurement system in the UK?

Answer 8

SI

Question 9

When was the use of the metric system sanctioned(given approval) for use in Britain by parliament?

Answer 9

in 1864 ! - 159 years ago !

Question 10

Continuously improving the definitions of units does what?

Answer 10

makes it
possible to have tighter tolerances and less waste
For example, gears will fit together better and therefore function more
efficiently and manufacturing will be able to rely on the dimensions of parts to
fit together.

Question 11

How are the new units different from old ones?

Answer 11

The new units are the same size as
previously but defined more precisely.

Question 12

New units as of may 20th 2019?

Answer 12

• Kilogram – now defined in terms of the Planck constant (h)
• Ampere – now defined in terms of the elementary charge (e)
• Kelvin – now defined in terms of the Boltzmann constant (k)
• Mole – now defined in terms of the Avogadro constant (NA)
  (subscript A)

Question 13

1m definition?

Answer 13

1 metre (m) = path travelled by light in 1/299 792 458 seconds
(vacuum)

Question 14

1s definition?

Answer 14

1 second (s) = duration of 9 192 631 770 periods of transition between
two levels of the ground state of the cesium 133 atom

Question 15

1kg definition?

Answer 15

the fixed numerical value of the Planck constant, ℎ,
to be 6.626 070 15 × 10-34 when expressed in the unit J s, which is
equal to kg m2 s−1, where the metre and the second are defined in
terms of the speed of light, c, and the hyperfine transition frequency of
the caesium-133 atom, ∆ν, respectively

Question 16

1a(ampere) definition?

Answer 16

the fixed numerical value of the elementary charge e to
be 1.602 176 634 × 10−19 when expressed in the unit C, which is equal
to A s, where the second is defined in terms of ∆ν.

Question 17

1 Kelvin definition?

Answer 17

the fixed numerical value of the Boltzmann constant kB to be
1.380 649 × 10−23 when expressed in the unit J K−1, which is equal to kg m2 s−2
K−1, where the kilogram, metre and second are defined in terms of h, c and ∆ν.

Question 18

1 candela(Cd) definition?

Answer 18

the luminous intensity of a monochromatic source emitting
at 540x10E12 Hz, with a radiant intensity of 1/683 watts per steradian

Question 19

1 mole definition?

Answer 19

One mole contains exactly 6.022 140 76 × 1023 elementary
entities. This number is the fixed numerical value of the Avogadro constant,
Na, when expressed in the unit mol-1 and is called the Avogadro number.

Question 20

Amount of substance definition?

Answer 20

The amount of substance, symbol n, of a system is a measure of the number
of specified elementary entities. An elementary entity may be an atom, a
molecule, an ion, an electron, any other particle or specified group of
particles.

Question 21

What are the two supplementary SI units?

Answer 21

Radian and Steradian