Gauss - Unit of Measurement

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Relation Between Gauss and Tesla

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In the CGS system or the centimeter gram second system of various physical units, gauss is the unit of magnetic induction. Generally, an electromotive force will be induced by the application of magnetic flux density. One gauss is equivalent when due to magnetic flux density, one abvolt or 10-8 volts of electromotive force is induced in a wire’s every linear portion or centimeter. Assume that the wire is moving at a speed of one centimeter per second laterally at ninety degrees to the magnetic flux. All the magnets are usually rated in terms of gauss. The symbol G is used to indicate this unit of measurement which measures magnetic flux density or magnetic induction.

Terminology of Gauss

As we already know gauss is the unit of magnetic induction. The unit was named after a German scientist by the name of Carl Friedrich Gauss. Previously this particular term was applied for magnetic field strength which was before the year 1932. Now the unit for magnetic field strength is oersted in the centimeter gram second system. But even now some people say that the magnetic field strength of the Earth is about one gauss. Carl Friedrich Gauss was a well-known nineteenth-century mathematician. The research and development of a magnetometer were highly contributed by him. 

Gauss and Tesla

It’s very important for anyone studying physics to know the interconversion from gauss to tesla and vice versa. But before that, it is important to understand these two terms. Gauss is derived from the Gaussian system of units which was inherited from the centimeter gram second system. The CGS system was furthermore succeeded multiple times to finally superseded by the International System of Units or the SI system. Hence, all the standard bodies deprecated the use of gauss as a unit. Although it is still used in various fields of science. Tesla is the SI unit of magnetic induction. The conversion from gauss to tesla is pretty simple. All you need to do is divide by 10000. One tesla is equivalent to 10000 gausses. It also states that 1 gauss is equal to 10-4 tesla.

Gauss and Magnetism

One maxwell per square centimeter is equivalent to one gauss. 1 gauss is equal to 10-4 Weber per meter square. The field strength of any magnetic material can be determined using the gauss gauge. The magnetic field strength is often measured using the tesla unit and not in the gauss unit. But this is not technically correct. It is because the definition of magnetic field strength and magnetic flux density is not the same. Although both are denoted by the same letter B. The units of magnetization of a ferromagnetic substance or remanence of any permanent magnet are also measured in terms of tesla and gauss. Remanence is also known as the strength of any magnet. 

Gauss Unit Physical Principles

Along with Wilhelm Eduard Weber, one of the famous physicists, Gauss framed the centimeter gram second system or CGS system. It is very similar to the modern SI system and is known as a standard unit control. The basic units of the CGS system form the gauss unit of magnetic flux. For length, it uses the unit of a centimeter, for the time it uses a unit of second, and for mass, it uses a unit of grams. Back in Germany until 1970, gauss was not any legal unit or entity in metrology. However, gauss is highly used in astrophysics. The legal unit of magnetic flux density in the SI unit is tesla and the relation between gauss and tesla is also pretty simple and important. One Newton per meter ampere is also equivalent to one tesla. 

Some Typical Values in Gauss

Let’s look at some of the typical values in the unit gauss. 

  • The surface magnetic field of the Earth - 0.25 to 0.60G.

  • Core magnetic field of the Earth - 25G.

  • Strength of a NIB magnet- 10000 to 13000G.

  • Electrodynamic quantum threshold magnetic strength - 4×1013 G.

  • Newborn magnetars magnetic field - 1015G.

  • Magnet field strength inside an MRI or magnetic resonance imaging machine- 3000 to 70000G.

  • Magnetic field strength within a sunspot – 1500G.

  • Transformers require high permeability alloys of iron which has a saturation of about 16000 to 22000G. 

Did You Know?

  • The magnetic field strength of a normal refrigerator magnet is around 50G.

  • Metric prefixes can be easily combined with the gauss such as milli gauss.

  • 4π × 10-3 oersted is equivalent to one ampere per meter.

  • Magnetic flux density is the number of field lines passing through a particular closed surface area.

FAQ (Frequently Asked Questions)

1. What do you mean by Tesla?

Answer: Tesla is the legal unit accepted by all the standard bodies for magnetic flux density or magnetic induction. It is the SI unit or International System of Units that follows the meter kilogram second system order of various physical units. Tesla can be converted to gauss and vice versa. One tesla is equivalent to 10000 gausses. It is also equivalent to one Weber per meter square. Gauss is generally useful with smaller magnetic fields. But Tesla, on the other hand, is potentially useful for greater and stronger magnets and their fields. It was named after the famous scientist Nikola Tesla. Hence, to sum up, tesla is generally the SI unit used for magnetic energy measurement.

2. What is meant by Field Strength in Physics?

Answer: Any region where a particular force affects all the points in the region is known as a field. We can find or experience field strength everywhere around us. A paper clip is automatically pulled towards a magnet if it is kept in the vicinity of the magnetic field surrounding the magnet. Similarly, two opposite magnetic poles attract while two like magnetic poles repel from each other when they are kept in each other’s magnetic field. An electric charge similarly produces an electric field. If any other charge is kept in this field then it may attract or repel. Objects fall on the Earth’s surface as a result of the gravitational field. Generally, the closer the lines of a field are, the stronger will be the field.