Homework

 

CHAPTER 7 ELECTRICAL ENERGY 142-153

DO INVESTIGATION 1 WITH A PARTNER pg 144

Write a sentence or two saying what you have found out about batteries, bulbs and switches

Chemical reactions of the battery allow electricity to flow around the circuit to light up the bulb. Switches can open and close a circuit. The current can be allowed to flow or interrupted.

Write your own notes on Electric Circuits, Electric current and measuring electric current.

A circuit is any arrangement that allows for electrical current to flow. It is the path on which electricity flows. Electrical current can be either direct current or alternating current. It is the movement of electrons from the negative to the positive. Electric current can be measured using ammeters. Oscilloscopes, voltmeters and digital multimeters are also used.

Write in your own words what conductors and insulators are, resistors and resistance and answer questions 1-8 pg 147

Conductors do not resist the flow of electricity and insulators have high electrical resistance.

Resistors are materials that do not completely inhibit the movement of electrons. Resistance is the measure of how well the electrons are stopped from moving.

1.      An electric current is a flow of electric charge involving the movement of electrons.

2.      aA conductor allows electrons to flow freely whereas an insulator limits it from doing so. b Electrical conductors include copper and aluminium. Insulators include rubber-like polymers and most plastics.

3.      aA path for electricity is called a circuit.

b A switch lets you open and close a circuit.

c The movement of electrons in a wire is called an electric current.

d Substances which do not allow an electric current to flow through them are called non-conductors.

e Metals are good conductors because they allow an electric current to flow through them.

f The more current there is flowing around a circuit, the brighter a bulb glows.

g If the resistance in a circuit increases, the current slows.

h A conductor has little resistance, while an insulator has high resistance.

4.      B and C will work as the wires must touch both the side and the bottom of the bulb. A and D are not connected properly.

5.      Electric current in a circuit is measured using an ammeter. The unit used to measure current is amperes (abbreviation amps, symbol A) or milliamps.

6.      The coating of the wire must be removed from the point where it is connected to a part of the circuit as it is an insulator and will prevent the electricity from flowing smoothly.

7.      Wires become hot when an electric current flows through it as it has resistance.

8.      The batteries produce electricity which flows around the electric circuit as an electric current. The switch can move and connect or disconnect the circuit. The insulating case is usually made of plastic and can insulate the electricity that flows along the side. The filament of the light bulb has high resistance and glows brightly when the current passes through it. The reflector helps direct the light to wherever the designer of the torch wants it to go.

Page 155 Over to you

1.      a Voltage is measured in volts (V)

b In a series circuit, the same current flows through all parts of the circuit.

c If you increase the voltage in a circuit, the current increases with it.

d If you increase the resistance in a circuit, the current decreases.

e A rheostat is an electrical device whose resistance can be changed.

2.      The difference between electric current and voltage is

3.      After a battery has gone flat, all the energy that was once stored in it

4.      A 6V battery connected in series with two bulbs would cause a 3 volt drop across each bulb.

Comments

Post a Comment

Popular posts from this blog

reverse-engineering

  Whether it's rebuilding a car engine or diagramming a sentence, people can learn about many things simply by taking them apart and putting them back together again. That, in a nutshell, is the concept behind reverse-engineering—breaking something down in order to understand it, build a copy or improve it.   A process that was originally applied only to hardware, reverse-engineering is now applied to software, databases and even human DNA. Reverse-engineering is especially important with computer hardware and software. Programs are written in a language, say C++ or Java, that's understandable by other programmers. But to run on a computer, they have to be translated by another program, called a compiler, into the ones and zeros of machine language. Compiled code is incomprehensible to most programmers, but there are ways to convert machine code back to a more human-friendly format, including a software tool called a decompiler.   Reverse-engineering is used for m...
Read more

Australian Icons Research

  Australian Icons Research- Why and How is Qantas Airlines Iconic? In March 1919, W Hudson Fysh and Paul McGinness became interested in a competition sponsored by the Government. They were unable to receive funding, and so, on 18 August 1919, in a Model T Ford, they began an assignment from the Defence Department to check a different competition route. It was during these 51 days when their determination grew to allow outback Queenslanders and people of North Australia have access to a more reasonable way of life. The key to this was air transport. Fergus McMaster, a wealthy grazier who was friends with McGinness, was the primary supporter of this new idea. He was Chairman in the beginning. The formation of the original Qantas company (Queensland and Northern Territory Aerial Services Limited.) was in 16 November 1920. The well-known ‘QANTAS’ was created from the acronym of this first name. Joy riding and demonstration flights were undertaken with two expertly modified old plane...
Read more

My Workplace Reflection

  My Workplace Reflection Using the results of your Employability Skills audit describe how one or more of your capabilities were developed through the work experience program. If possible, use specific examples that relate to each capability. My Literacy Capability was developed the most during the program. All the tasks that I performed required me to first fully understand the instructions. Working with, and serving customers was also a new experience and required me to understand their problems and keep them happy by suggesting alternative ways. Understanding the customer and talking to them in a friendly way was all that was expected of me at that stage. My Critical and Creative Thinking Capability was developed when I ran into small problems in various tasks. In some cases I was unable to come up with a solution and hence, asked for help. Initiative in solving problems was a relatively minor aspect and so it can be developed further. Working in a public library, one c...
Read more