Assignment:
It is a physic quiz on website. Some questions on this quiz may involve some calculation.
There are the summary of this chapter:
Electricity and Magnetism:
• Protons and Electrons have a property called Charge, which makes them attract and repel. This is called the Electric or Electrostatic Force.
• When Charges move around, we refer to it as Electric Currents.
• The Voltage of the Electricity is related to the Energy of the moving Charges, and the Current is related to their number.
• When Current flows through a material, some Energy is lost and changed to Heat. This is called Resistance.
• Unless the material is a Superconductor, which have no Resistance.
• Moving Charges (Currents) experience another force called the Magnetic Force.
• In a Permanent Magnet, the moving charges are due to the microscopic motion of Electrons
• In most materials, the motion of the Electrons is random. If the Electrons move in the same direction, you get a Magnet
• When a Magnetic material (such as Iron) is placed near a Magnet, the Electron motion aligns, the material temporarily becomes a Magnet, and it is attracted.
• Ordinary Electric Currents also act like Magnets, and are called Electromagnets
• Electric Motors convert Electrical Energy to mechanical motion
• Electric Generators convert mechanical motion to Electrical Energy
• Transformers change the Voltage of Electricity
• Magnets can be used for applications such as Magnetic Recording (computer hard drives) and Rail Guns