Electric Current
This presentation is the property of its rightful owner.
Sponsored Links
1 / 20

Electric Current PowerPoint PPT Presentation


  • 31 Views
  • Uploaded on
  • Presentation posted in: General

Electric Current. What is an electric current?. To understand what an electric current is, we must first learn the structure of (1). What is an electric current?. atom.

Download Presentation

Electric Current

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Electric current

Electric Current


Electric current

What is an electric current?

To understand what an electric current is, we must first learn the structure of (1).

What is an electric current?


Electric current

atom


Electric current

Matter is made up of atoms. An atom consists of a (2) (+) and (3) (-). Sometimes electrons can escape from an atom and move freely with the conductor. These electrons are called (4) electrons.

free electrons

nucleus

atom

electrons


Electric current

A piece of copper wire contains many free electrons. When the wire is not connected to a dry cell, the free electrons move in different directions.

free electrons moving in different directions

atoms in the copper wire


Electric current

However, when the ends of the copper wire are connected to a dry cell, the free electrons move in the (5)direction. This flow of free electrons is called an electric current.

flow of free electrons


Electric current

SUMMARY

The electric current in a metal wire is a flow of .

F(6)____

e (7)_____

Activity 8(c)


Electric current

Measuring

electric

current


Electric current

Ammeter

(安培計)


Electric current

What is the unit

of electric current?


Electric current

Ampere

(安培)

(A)

Milliampere

(mA)(毫安培)


Electric current

We use an (8) to measure the size of an electric current. The unit of electric current is (9). The symbol of the unit is (10).

Small currents are measured in milliampere (mA).

Experiment 8.4

Do you know?

Do you know?

Do you know?

Activity 8(d)


Answers

1. atom

2. nucleus

3. electrons

4. free

5. same

6. free

7. electrons

8. ammeter

9. ampere

10. A

Answers:


Electric current

Analogy of

electric circuit


The water pipe system

The water pipe system


The water pipe system1

Water pump

Water pipe

Flow of water

Water turbine

Tap

Water

The water pipe system:


The electric circuit

The electric circuit


The electric circuit1

dry cell

Connecting wire

Light bulb

Flow of free electrons

Switch

Free electrons

The electric circuit:


Analogy

Analogy


Analogy of electric circuit with water pipe system

Water

Water pipe

Water turbine

Tap

Water pump

Flow of water

Free electrons

Connecting wires

Light bulb

Switch

Dry cell

Flow of _____ _____

Analogy of electric circuitwith water pipe system


  • Login