Week - 1 - Consistency of Units
Objective:- Write a detailed report on unit conversion with calculations and there units.
1) Convert Kg cm ms
MASS 1kg = 1000gms.
LENGTH 1m = 100cm.
TIME 1s = 1000ms
FORCE = Force is an external agent capable of changing the state of rest or motion of a particular body. It has a magnitude and a direction.
unit = kg·m/s2
STRESS = It is defined as internal resistance offered by the body or force per unit area.
unit = N/m^2.
Value of the following measurements is given as follows:
- MASS 1kg
2.LENGTH 1m
3.TIME 1s
4.FORCE 1N
5.STRESS 1Pa
6.ENERGY 1Nm
7.DENSITY 1Kg/m3
8.YOUNG'S Modulus 210GPa
9.Velocity 56.33KMPH
10.GRAVITY 9.8m/s2
Now, here are a few systems of units:
Kg cm ms
Kg cm s
gm mm ms
kg m s
g cm s
g cm us
g mm s
ton mm s
slug ft s
kg mm s
g cm ms
kg mm ms
EXPLANATION 0F UNITS
- Units are most basic aspects of any measurements.
- they are arbitrarily chosen and internationally accepted.
Categories of units
- Fundamental units
- Some units are arbitrarily chosen to be fundamental.
- They become foundation for system.
- Every other units is derivable from them.
- Derived units
- Units derived from the fundamental units by multiplication and division are called derived units.
Example LENGTH=SPEED*TIME
In this length is a derived unit
At different points of time different systems of measurement were pervasive
- CGS SYSTEM
- Centimeter for length
- gram for mass
- second for time
- FPS SYSTEM
- Foot for length
- pound for mass
- second for time
- MKS SYSTEM
- Meter for length
- kilogram for mass
- second for time
EXAMPLE FOR CGS, MKS, FPS SYSTEMS
FORCE=MASS*ACCERLATION
SI UNIT-NEWTON
- F=M*a m=1kg a=1m/sec^2
=1kg*1m/s^2
1N=1kg.m/s^2
CGS
1DYNE=1gm * 1cm/s^2
1Newton=1kg * 1m/s^2
=1000gm * 100 cm/s^2
=10^5 gm cm/s^2
1N =10^5 dyne
MKS
1KGF=1kg * 9.81 kg.m/s^2
1kgf=9.81N
FPS
1LBF=1lb * 32.17 ft/s^2
g=9.81m/s^2
1m=3.28 ft
1N=9.81 * 3.28 ft/s^2
=32.17 ft/s^2
Calculation for conversion from SI unit to gm/mm/ms unit
MASS 1 Kg = 1000 gm
LENGTH 1 m = 1000 mm
TIME 1 s = 1000 ms
- FORCE
- 1N = (1Kg * m)/s^2
= (1000 gm * 1000 mm) / (1000 ms *1000 ms)
= (1 gm * mm ) / ms^2
Conversion factor=1
- STRESS
- 1Pa = N / m^2 =1 kg / m · s2.
= 1000gm/1000mm (1000 ms *1000 ms)
= 10^-6 gm /mm*ms^2
Conversion factor=10^-6
- ENERGY
- 1Nm = { (1Kg * m^2)/s^2 }
=1000gm*1000mm*1000mm/1000ms*1000ms
= 10^3 gm*mm^2/ms^2
Conversion factor=10^3
- DENSITY
- 1Kg/m3 = 1000 gm /1000mm*1000mm*1000mm
= 10^3 gm/ 10^9 ms^3
= 10^-6gm/ms^3
Conversion factor=10^-6
- YOUNG’S Modulus
- 210GPa = 210 X [10^9 X (N / m^2)] { 1 GPa = 10^9 X (N / m^2)}
= 210 X [10^9 X (10^-6 gm /mm*ms^2)]
= 210 X 10^3 gm/mm*ms^2
= 210000 gm/mm*ms^2
Conversion factor=10^3
- Velocity
1KMPH = 10^6mm / (3600 *1000 ms) { 1KM = 10^6mm}
= 10/36 = 0.277 mm/ms { 1hr = 3600 *1000 ms}
56.33KMPH = 56.33 x 0.277
56.33KMPH = 15.64 mm/ms
Conversion factor=1
- GRAVITY 9.8m/s
- 1 m/s2 = 1000 mm/(1000 ms X 1000 ms)
= 10^-3 mm/ms^2
9.8m/s2 = 9.8 X 10^-3 mm/ms^2
Conversion factor=10^-3
|
Unit system |
Mass |
Length |
Time |
Force |
Stress |
Energy |
|
SI Unit kg m s |
1kg |
1m |
1s |
1 N = 1 kg*m/s2 |
1 Pa = 1 kg/(m* s2) |
1 J = 1Nm = 1 kg*m2/s2 |
|
kg cm ms |
1kg |
102cm |
103ms |
10-4 kg*cm/ms2 |
10-8 kg/(cm*ms2) |
10-2 kg*cm2/ms2 |
|
kg cm s |
1kg |
102cm |
1s |
102 kg*cm/s2 |
10-2 kg/(cm*s2) |
104 kg*cm2/s2 |
|
g mm ms |
103g |
103mm |
103ms |
1 g*mm/ms2 |
10-6 g/(mm*ms2) |
103 g*mm2/ms2 |
|
g cm s |
103g |
102cm |
1s |
105 g*cm/s2 |
10 g/(cm*s2) |
107 g*cm2/s2 |
|
g cm μs |
103g |
102cm |
106μs |
10-7 g*cm/μs2 |
10-11 g/(cm*μs2) |
10-5 g*cm2/μs2 |
|
g mm s |
103g |
103mm |
1s |
106 g*mm/ s2 |
1 g/(mm*s2) |
109 g*mm2/s2 |
|
Ton mm s |
10-3ton |
103mm |
1s |
1 ton*mm/s2 |
10-6 ton/(mm*s2) |
103 ton*mm2/s2 |
|
slug ft s |
0.068slug |
3.28 ft |
1s |
0.2246 slug*ft/ s2 |
0.0208 slug/(ft*s2) |
0.7366 slug*ft2/s2 |
|
kg mm s |
1kg |
103mm |
1s |
103 kg*mm/s2 |
10-3 kg/(mm*s2) |
106 kg*mm2/s2 |
|
g cm ms |
103g |
102cm |
103ms |
10-1 g*cm/ms2 |
10-5 g/(cm*ms2) |
10 g*cm2/ms2 |
|
kg mm ms |
1kg |
103mm |
103ms |
10-3 kg*mm/ms2 |
10-9 kg/(mm*ms2) |
1 kg*mm2/ms2 |
Conclusion:
The unit conversion was done for a different systems of units.