What are Resistors?

Targets

At the end of this Unit you should be able to answer the following questions 

1. What are electricity and magnetism, and how can they be used safely?

1.1 What is electricity?

1.2 What is magnetism, and how is it related to electricity?

1.3 What are the dangers of electricity, and how can it be used safely?

2. How can electricity be controlled and used?

2.1 How is the electricity we use daily measured and paid for?

2.2 Do all materials allow electricity to flow through them?

2.3 How can we understand, design, and control electrical pathways?

2.4 How can we change circuits to control the amount of electricity that flows?

3. How can we use electrical circuits to build devices?

3.1 How can electrical technology be used to build devices and solve problems?

targets



Life in Canada would be very uncomfortable if we did not have heat! Thankfully, we can use heaters and furnaces in the long, cold winter to keep warm. Many types of heaters run on electricity, but there is something very interesting about the way they use electricity. The heating coils that glow red hot in a heater are poor at letting electricity flow. You have to wonder why heaters are made this way? Wouldn't it make more sense to use heating coils that are good at letting electricity flow? 


Resistors

A resistor device can be placed on a wire so that the electrons bunch up when they enter one side of the resister and cause a high pressure or voltage.  On the other side of the resister where they exit or leave the resistor there is a low pressure or voltage. 

  Video

Watch first seven minutes of the Resistors to learn more (Do not watch the formulas).

or 
So what about the heater? The heater coils are made of a metal that has high resistance.  They make the flow of electricity difficult, changing a lot of the electrical energy into heat.