Overview

Science standards 4.3 provide students with a strong foundation in the characteristics of electricity and simple circuits. Students in fourth grade construct series and parallel circuits and make electromagnets. Standard PS.11 is intended to provide a more in-depth and mathematical focus on circuits, current, static electricity, and the relationship between electricity and magnetism. It is intended that students will actively develop scientific investigation, reasoning, and logic skills, and the nature of science (PS.1) in the context of the key concepts presented in this standard.

 

PS.11          The student will investigate and understand basic principles of electricity and magnetism. Key concepts include

a)      static electricity, current electricity, and circuits;

b)     relationship between a magnetic field and an electric current;

c)      electromagnets, motors, and generators and their uses.; and

d)     conductors, semiconductors, and insulators.

 

Essential Understandings

Essential Knowledge, Skills, and Processes

The critical scientific concepts developed in this standard include the following:

  • Several factors affect how much electricity can flow through a system. Resistance is a property of matter that affects the flow of electricity. Some substances have more resistance than others.
  • Friction can cause electrons to be transferred from one object to another. These static electrical charges can build up on an object and be discharged slowly or rapidly. This is often called static electricity.
  • Electricity is related to magnetism. Magnetic fields can produce electrical current in conductors. Electricity can produce a magnetic field and cause iron and steel objects to act like magnets.
  • Electromagnets are temporary magnets that lose their magnetism when the electric current is removed. Both a motor and a generator have magnets (or electromagnets) and a coil of wire that creates another magnetic field.
  • A generator is a device that converts mechanical energy into electrical energy. Most of the electrical energy we use comes from generators. Electric motors convert electrical energy into mechanical energy that is used to do work. Examples of motors include those in many household appliances, such as blenders and washing machines.
  • A conductor is a material that transfers an electric current well. An insulator is material that does not transfer an electric current. A semiconductor is in-between a conductor and an insulator.
  • The diode is a semiconductor device that acts like a one way valve to control the flow of electricity in electrical circuits. Solar cells are made of semiconductor diodes that produce direct current (DC) when visible light, infrared light (IR), or ultraviolet (UV) energy strikes them. Light emitting diodes (LED) emit visible light or infrared radiation when current passes through them. An example is the transmitter in an infrared TV remote or the lighting course behind the screen in an LED TV or notebook computer screen.
  • Transistors are semiconductor devices made from silicon, and other semiconductors. They are used to amplify electrical signals (in stereos, radios, etc.) or to act like a light switch turning the flow of electricity on and off.

In order to meet this standard, it is expected that students will

  • design an investigation to illustrate the effects of static electricity.
  • construct and compare series and parallel circuits.
  • create an electromagnet and explain how it works.
  • explain the relationship between a magnetic field and an electric current.
  • construct simple circuits to determine the relationship between voltage, resistance, and current.
  • compare and contrast generators and motors and how they function.
  • identify situations in everyday life in which motors and generators are used.
  • provide examples of materials that are good conductors, semiconductors, and insulators.
  • identify current applications of semiconductors and their uses (e.g., diodes and transistors).