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Does Gravity Apply To A Physics Teacher Salary?

Most, if not all, students can lay claim to a teacher or two who bore some influence in their passage through education. Perhaps one who opened up their minds to the laws of physics or another who gave them insight into the works of Shakespeare. There are probably countless cases of teachers and students passing through numerous generations of teaching and learning, having cause and effect upon one another’s lives.

If one is moved or called into the teaching profession with a penchant for science, many opportunities await suitably trained applicants to fill vacant positions in schools throughout the nation. As the need stretches across all disciplines of science, one can step up to the challenge of being a Physics teacher. Salary, as expected, is a matter of great interest in line with one’s passion for Newton and his laws. Due to the spread of the teaching community over numerous states and economical influences, the ability of employers to pay also differs. In more affluent environments such as prominent establishments in larger cities, their teaching staff probably receive a higher pay check as compared to the motley crew of a science department in a lesser developed neighborhood. Although this may topple the scales of injustice, it is an apparent fact that may not see much change as yet.

In the event one is based in an environment of latter mention, there is still hope to pursue this career without having to resort to living on air, water and sunshine. By studying and obtaining a specialty within the discipline, one can draw a specialist physics teacher salary. This presents an opportunity to delve deeper into the laws of physics as most are qualified to only cover the general aspects. Opting for a contractual appointment may present offers of a better package. Alternatively, part time teaching opportunities are aplenty for those who prefer to keep their day jobs and conduct remedial science classes after hours.

Chris is the writer of this article , you can visit us for more information on Teacher Salaries and Colorado Teacher Salary Schedule.
 March 29th, 2017  
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 Life  
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Dec
18

Specific Gravity Value

Introduction to Specific gravity value

Relative density or specific density value of a substance is the ratio of the substance density to the density of water. Since its the ratio, specific gravity of a substance is a unit-less quantity. It is defined so that the value remains same even when we use different system of units such as ft-lb.

Examples of Specific Gravity Value

Example 1

An liquid substance has a mass of 11.5 g and occupies a volume of 13.4 ml. Find the density of the liquid substance.

Solution

The density can be calculated as

? = [(11.5 g) / (1000 g/kg)] / [(13.4 ml) / (1000 ml/l) (1000 l/m3) ]

= (11.5 10-3 kg) / (13.4 10-6 m3)

= 858.20 kg/m3

The Specific Gravity value or relative density value is a dimensionless number defined as the ratio of density of the material to the density of water at a certain temperature.

Specific Gravity value can be expressed as

SGV = = ? / ?H2O (3)

where

SGV = specific gravity value

? = density of fluid or substance (kg/m3)

?H2O = density of water (kg/m3)

It is common to use the density of water at 4 oC (39oF) as reference as the density of water is at the highest at this temperature- 1000 kg/m3 or 62.4 lb/ft3.

Example 2.

If the density of iron is 7850 kg/m3,what is the specific gravity of iron ?

Solution:

SG = (7850 kg/m3) / (1000 kg/m3)

= 7.85

Specific Gravity Values : Table

Specifice gravity values of some common substance are given below

Barium

3.62

Barium sulfate

4.5

Bentonite

2.4

Beryllium

1.848

Bismuth

9.79

Boron

2.34

Brass, cast-rolled

8.4 – 8.7

Bronze, aluminum

7.7

Calcium carbonate

2.7

Carbon

2.26

Cement

3.0

Cerium

6.77

Cesium

1.873

Chromium

7.19

Chromium dioxide (Cr203)

5.22

Chromium oxide (Cr02)

4900 kg m-3

Clays

2.6

Coal slag

2.7

Cobalt

8.92

Copper, cast-rolled

8.8 – 8.95

Copper ore, pyrites

4.1 – 4.3

Diamond

2.26

Dolomite

2.9

Dysprosium

8.55

Erbium

9.066

Europium

5.244

Ferrosilicon- 15%

6.7-7.1

Flint stones/ pebbles

2.4 – 2.6

Gadolinium

7.9

Gallium

5.91

Germanium

5.32

German silver

8.58

Glass beads

2.5

Gold, cast-hammered

19.25 – 19.35

Gypsum

2.3

Hafnium

13.31

Hematite, specular

5.4

Holmium

8.795

Ilmenite

4.5- 5.0

Indium

7.31

Iodine

4.93

Iridium

21.78 – 22.65

Iron carbonate

3.9+

Iron, gray cast

7.03 – 7.13

Iron, cast, pig

7.2

Iron, wrought

7.6 – 7.9

Iron, spiegeleisen

7.5

Iron, ferrosilicon

6.7-7.3

Iron ore, hematite

5.2

Iron, ore, limonite

3.6 – 4.0

Iron ore, magnetite

4.9 – 5.2

Iron ore, specular

5.4

Iron slag

2.5 – 3.0

Lanthanum

6.17

Lead

11.34

Lead ore, galena

7.3 – 7.6

Lead oxide (yellow)

9.5 – 9.9

Limestone

2.8

Lithium

0.53

Lutetium

9.84

Magnesium

1.738

Manganese

7.35

Manganese ore, pyrolusite

3.7 – 4.6

Mercury

13.534

Molybdenum

10.22

Monel metal, rolled

8.97

Nickel

8.9

Niobium

8.57

Osmium

22.61

Palladium

12.02

Phosphorus

2.34

Platinum

21.5

Potassium

0.856

Praseodymium

6.77

Quartz sand

7.00

Rhenium

21.02

Rhodium

12.41

Rubidium

1.532

Ruthenium

12.45

Salt

2.2

Samarium

7.52

Sand, silica

2.6

Sand, Quartz

7.0

Scandium

2.989

Selenium

4.28

Sialon

3.26

Silicon

2.33

Silicon carbide

3.1

Silicon nitride

3.2

Silver, pure

10.4 – 10.6

Sodium

0.968

Steatite beads

2.6 – 2.7

Steel, carbon

7.8

Steel, chrome

7.8

Steel, cold-drawn

7.83

Steel, machine

7.80

Steel, 440C stainless

7.7

Steel, tool

7.70 – 7.73

Strontium

2.64

Sulfur

2.07

Tantalum

16.69

Tellurium

6.24

Terbium

8.27

Thallium

11.85

Thulium

9.32

Tin, pure

7.2 – 7.5

Tin ore, cassiterite

6.4 – 7.0

Laser: An artificial light source which has many features is laser. When a light is exposed into a medium , there are three processes can happen and have struggle with the medium.

They are,

Stimulated absorption
Spontaneous emission
Stimulated emission

In emission process the atoms have a movement from the excited state to the ground state where as in absorption process the movement of atom is from the ground state to the absorption state.

Spontaneous emission:

Spontaneous emission:

In this process of spontaneous emission the atoms in the state of excited state E2 returns to the lower state of ground state. That is the atom moves from the higher state to lower state. It is happening by emitting the photon having an energy hv with out the need of external action.

Spontaneous emission is defined as the emission of radiation which is not due to any external force.

Representation of spontaneous emission:

This spontaneous emission is considered as an uncontrollable and random process.

Stimulated emission and absorption:

Stimulated emission:

Stimulated emission is same as the spontaneous emission but it is happening due to some force.

In this there is a connection among the atom in excited state and the photon. The photon can trigger an atom, to move from excited state to the ground state E1. This movement can form a new photon similar to the old photon such as frequency, phase, direction and propagation. In laser performance stimulated process is act as a key factor.

Representation of stimulated factor:

As in figure before emission there is only one photon and the atom is in excited state E2. During stimulation the photon can trigger an atom and transfer it to the lower ground state E1. This process is otherwise known as induced emission.

Stimulated emission is more powerful because it can be multiplied by a chain reaction and leads to the coherent.

Stimulated absorption:

Stimulated absorption is the reverse process of stimulated emission. In this an atom in the ground state E1 absorb a photon of energy hv and goes to the excited state E2. An energy of the photon is equivalent to E2 – E1.

As in figure after absorption of photon the atom moves from ground state to excited state.

Titanium

4.506

Titanium dioxide, Anatase

3.77

Tin, 100% Pure

7.29

Tungsten

19.25

Tungsten carbide

14.29

Uranium

18.7

Vanadium

6.11

Water, fresh

1.0

Ytterbium

6.97

Yttrium

4.47

Zinc, cast-rolled

6.9 – 7.2

Zinc, ore, blend

3.9-4.2

Learn more on aboutElectromagnetic Spectrum Wavelengths and its Examples. Between, if you have problem on these topics Electromagnetic Waves Consist of

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 December 18th, 2016  
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