Essays Tagged: "Electric current"

Voltage - Current relationship in a DC circuit

wn in this relation, V represent voltage which is the potential difference across the two ends of a electrical conductor and between which an electric current, I, will flow. The constant, R, is called ... it directly provided that the remaining variable V and I is known. A resistor is a piece of electric conductor which obeys Ohm's Law and has been designed to have a specific value for its resi ...

(3 pages) 59 0 3.3 Mar/1996

Subjects: Science Essays > Physics

Superconductivity

blems and some examples of its uses.CONDUCTIVITYConductivity is the ability of a substance to carry electricity. Somesubstances like copper, aluminium, silver and gold do it very well. They arecalled ... like copper, aluminium, silver and gold do it very well. They arecalled conductors. Others conduct electricity partially and they are calledsemi-conductors. The concept of electric transmission is ve ...

(6 pages) 72 0 3.4 Mar/1997

Subjects: Science Essays > Physics

DNA electropherises

el. The DNA samples are loaded using a measuring instrument called a micropipeter. There is then an electric current passed through the gel to separate the DNA fragments. The current separates the DNA ... ergy in nuclear plants so strict safety precautions are taken. Some research shows that exposure to electric magnetic fields, such as power lines and electric appliances, is a possible risk factor. Mo ...

(4 pages) 42 0 4.7 Feb/1997

Subjects: Science Essays > Genetics & Genome Projects

Talking about investigating the resistance of a wire

th of a wire affects the resistance of it.TheoryResistance is a force, which opposes the flow of an electric current around a circuit so that energy is required to push the charged particles around th ... t the flow of particles if the wires are either very thin or very long. E.g. the filament across an electric bulb is quite thin as needs to resist the flow of particles for the bulb to glow.Resistance ...

(4 pages) 74 0 4.6 Nov/2002

Subjects: Science Essays > Physics

Solar cell technology.

erel observed that shining light on an electrode submerged in a conductive solution would create an electric current. Later in 1877, Charles Fritts constructed the first true solar cell by using junct ... hotovoltaic modules, increase module efficiencies, decrease direct manufacturing costs, and improve electric power production costs. Pv for Utility Scale Applications (PVUSA), a national public-privat ...

(10 pages) 119 2 4.2 Nov/2003

Subjects: Science Essays

How an electric generator works and what parts it consists of.

An electric generator is basically an electric motor working backwards. An electric motor converts elec ... otor working backwards. An electric motor converts electrical energy into mechanical energy, and an electric generator converts mechanical energy into electrical energy. An electric generator looks al ... nverts mechanical energy into electrical energy. An electric generator looks almost identical to an electric motor. Each consists of a loop that is able to rotate in a magnetic field. The electric mot ...

(2 pages) 62 0 3.7 Nov/2003

Subjects: Science Essays

Chemistry electrolysis coursework

It is known that by passing a constant electric current through an aqueous copper sulphate solution that the passage of ions through this s ... of any element deposited during electrolysis is directly proportional to the number of coulombs of electricity passed"Faraday's Second Law of electrolysis states that:"The mass of an element deposite ... araday's Second Law of electrolysis states that:"The mass of an element deposited by one Faraday of electricity is equal to the atomic mass in grams of the element divided by the number of electrons r ...

(5 pages) 57 0 4.5 Jan/2004

Subjects: Science Essays > Chemistry

Cloning-definitions, pros, cons.

a skin cell) from a donor. This combination of the two cells is then activated , mostcommonly by an electric current. If all of this goes well an embryo begins to develop.There are three types of scie ...

(6 pages) 65 0 3.0 Jan/2004

Subjects: Science Essays > Genetics & Genome Projects

Electro-Static Revision Notes

*Electric Current is a flow of electric charges, consisting of electrons. Two types of charges - posi ... (t)*Coulomb (C) is amount of charge passing a point when a current of an ampere flows for a second.*Electricity is conducted only through material soluble in water when in water, aqueous solutions and ... q is charge and r is distance - if more than two charges use vector addition - find the resultant.*Electric field is produced by a charge or a combination of charges. Forces are felt depending direct ...

(3 pages) 75 5 4.3 Feb/2004

Subjects: Science Essays > Physics

Acid

in your stomach to help digest food. Sulfuric acid is found in car batteries. Acids can conduct an electric current. Acids are also corrosive. When acids react with metals they form hydrogen gas. Whe ... olytes. When they are dissolved in water they produce a solution that contains ions and can conduct electricity. In 1884 Svante Arrhenius proposed that an acid be defined as a hydrogen-containing comp ...

(2 pages) 28 0 3.0 Mar/2004

Subjects: Science Essays > Chemistry

Investigating the rate of electrolysis. An investigation to find out what factors affect the rate of electrolysis of a solution containing copper (II) ions.

f electrolysis of a solution containing copper (II) ions.PlanIt is known that by passing a constant electric current through a copper sulphate solution the passage of ions through this solution result ... as in my previous years of schooling when using magnets I have found that opposite charges attract. Electricity is the flow of negatively charged electrons, when the copper ions come within contact of ...

(11 pages) 65 1 2.6 Mar/2004

Subjects: Science Essays > Chemistry

Electric circuit

Aim: To design a simple electrical circuit for Doctor's Surgery to let people know when to enter and also to research and le ... o to research and learn more about parallel and series circuits.IntroductionI am going to design an electric circuit for a Doctor's surgery.There are two types of circuit's Parallel circuit, and Serie ... ies circuit.First I am going to explain what a circuit is and what the differences they have are.An electric current is a flow of charge. The charges are given energy and made of flow using a cell or ...

(4 pages) 44 0 4.3 Apr/2004

Subjects: Science Essays > Engineering

Factors affecting the resistance of a wire

affecting the resistance of a wireIntroduction:Resistance is a force, which opposes the flow of an electric current around a circuit.Resistance is measured in Ohms. George Ohm discovered that a circu ... .Resistance is measured in Ohms. George Ohm discovered that a circuit sometimes resists the flow of electricity. He called this 'RESISTANCE.' He even came up with a rule for working out the resistance ...

(5 pages) 34 0 3.0 May/2004

Subjects: Science Essays

What Is Electrolysis

aving the artefact clean.ElectrolysisIn chemistry, the production of chemical changes by passing an electric current through a solution or molten salt (the electrolyte), resulting in the migration of ... at the cathode receive electrons to form hydrogen gas;ElectrolysisRemoval of unwanted hair using an electric current. It can be very effective in experienced hands, but is slow and therefore expensive.

(1 pages) 23 0 3.0 Jul/2004

Subjects: Science Essays > Physics

Electromagnetic Induction

the magnetic field about an electromagnet was made to grow and collapse by closing and opening the electric circuit of which it was a part, an electric current could be detected in a separate conduct ... ggregate of the lines intersecting a given area is called the magnetic flux. Faraday attributed the electrical effects to a changing magnetic flux.The necessity of motion to produce a current is due t ...

(9 pages) 45 0 4.3 Nov/2004

Subjects: Science Essays > Physics

The Resistance Of A Wire

the length of the wire.TheoryWhat is resistance?Resistance is a force which opposes the flow of an electric current around a circuit so that energy is required to push the charged particles around th ... st the flow of particles if the wires are either very thin or very long.e.g. The filament across an electric light bulb.How is it measured?The resistance of a length of wire is calculated by measuring ...

(3 pages) 24 0 4.3 Dec/2004

Subjects: Science Essays > Physics

Human Cloning

e DNA, then you fuse the egg with a cell from the human that you're copying. Then, with the help of electric current, you'll try to stimulate it to divide and become an embryo. You then take implant t ...

(2 pages) 62 2 3.0 Jan/2005

Subjects: Science Essays > Genetics & Genome Projects

The Periodicity of Hydrides in Groups 4 to 7

en transition metals and the hydrogen atoms depending on certain factors: temperature, pressure and electric current.When molecules change phases from liquid to gas, enough energy has to be applied to ...

(3 pages) 21 0 0.0 Apr/2005

Subjects: Science Essays > Chemistry

Federal Highway System

el-cell and hydrogen research was a boost for the emerging technology, which converts hydrogen into electric current while releasing steam as a byproduct.A few days later, Bush said he wants to see th ... is sitting on the shelf while Detroit dithers. Honda and Toyota are producing (fuel-efficient, gas-electric) hybrid vehicles today, the Big Three are not. Honda has stated that it is using the electr ...

(3 pages) 21 0 3.0 May/2005

Subjects: History Term Papers > North American History

Working of Electric Filament Heaters:

Appliances that heat up, such as a hair dryer, a clothes iron, toaster, electric toaster oven, or an electric space heater all work on the same idea. They change electrical ... n the same idea. They change electrical energy to heat energy.The devices all plug into a source of electricity. Electric current runs from your wall socket down the wire and into the appliance.Inside ... chromium. It has two features that make it a good producer of heat:Nichrome wire has a fairly high electrical resistance compared to something like copper wire, so even a short length of it has enoug ...

(1 pages) 18 1 2.5 Jun/2005

Subjects: Science Essays > Technology