Btec L3

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1. Describe the basic features of electricity at a fundamental level.

Ans: Electricity is the movement of electrons. As long as electrons in an atom are balance and revolve precisely in orbit around their sun or atom nucleus there is no electron flow or electric current in a wire. These atoms are the smallest particle into which an element can be divided without losing its property. A single atom consists of three basic components: a Proton, a Neutron and an Electron. An atom is similar to a small solar system, so is the nucleus in the centre of an atom. Protons and neutrons are contained within the nucleus. Electrons orbit around the nucleus which could be similar to planets orbiting around the sun. As an electrician I will also be dealing with insulators. An insulator is any material that stops the flow of electrons examples are rubber, glass and plastic. Conductors are the opposite of and insulator they are material that easily allows electrons to flow, like cooper, gold and silver. A material that has high resistance has low conductivity, this means that it doesn’t conduct current easily; likewise a material that has high resistance has high conductivity. Resistance is measured in units called Ohms. There are types of electricity, one is static electricity. Static electricity is the charges that are fixed in place unlike electrons in wires with voltages potential with no electron flow. Opposite electrical charges always attract each other, so these particles with opposite charges will tend to move towards each other. Like electrical charges always repel.

2. What part of cables are conductor and insulators.

Ans: The electrons of different types of atoms have different degrees of freedom to move around. With some types of materials, such as metals, the outermost electrons in the atoms are so loosely bound that they wildly move in the space between the atoms of that material by nothing more than the influence of room-temperature heat energy. Because the virtually unbound electrons are free to leave their respective atoms and float around in the space between adjacent atoms they are often called free electrons. This relative mobility of electron within a material is known as electric conductivity. Conductivity is determined by the types of atoms in a material (the number of protons in each atom’s nucleus, determining its chemical identity) and how the atoms are linked together with one another. Materials with high electrons mobility (many free electrons) are called conductors, while material with low electron mobility (few or no free electrons) is called insulators. Mainly the equal sides of material repel each other and opposite sides attract. A few common examples of conductors are silver, gold, aluminium, iron, steel and mercury. A few common examples of insulators are fiberglass, rubber, cotton, paper, wood, plastic, air and diamond.

3. Explain, in terms of charged particles, why some objects are electrically attracted to each other, while others repel each other.

Ans: These are the two fundamental principles of charges interactions used in static electricity; opposites attract and likes repel. There are also two types of electrical charges, those that contain more protons than electrons are positively charged and negatively charge. In contrast to the attractive force between two objects with opposite charges, two objects that are of like charge will repel each other. A positively charged object will use a repulsive force upon a second positively charged object but will attract negatively charged objects.

4. Describe the flow of direct current?

Ans: Direct current (DC) is the unidirectional flow of electric charge; which means the electrons flows in one directions usually maintained by a constant or uninterrupted voltage. The electric charge flows in a constant direction, distinguishing it from alternating current (AC). Direct current is produced by sources such as batteries, solar cells...
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