8.3.2-Electric Current and Simple Circuits

Chapter 3 Electricity

8.3.2-Electric Current and Simple Circuits

Essential Questions

1. What is the relationship between electric charge and electric current?

2. What are voltage, current, and resistance, and how do they affect each other?

electric currents

Let's recall last lesson.

• Static electricity is the buildup of electric charges.

• Opposite charges attract; like charges repel.

• Positively charged atoms have more protons

• negatively charged atoms have more electrons.

During a lightning...

• Electrons in the atmosphere jump down to pair with protons on the ground.

• 
  

• 
  

• 
  

What is an electric current?

The flow of electric charges through a conductor.

The difference between static electricity and electric currents.

Electric charges that build up on static electricity do not flow. Instead the charges jump between two objects.

electric currents is a flow of electrons like a stream of water through a conductor like copper or metal.

Multiple Choice

True or False
A positively charged object has lost electrons

• True
• False

Multiple Choice

Static electricity is 

• The balance of electrical charge on an object
• The imbalance of electrical charge on an object
• The discharge of electrical charge
• The build up of protons in the nucleus of an atom 

Multiple Choice

What charge does an electron have?

• negative (-)
• positive (+)
• neutral or no charge (0)

Multiple Choice

What charge does a proton have?

• negative (-)
• positive (+)
• neutral or no charge (0)

Electric Current

• When Electric charges are made to flow through a material, they produce an electric current

• An electric current is the continuous flow of electric charges through a material

• The amount of charge that passes through a wire at a given period of time is the rate of electric current

• The unit for the rate of electric current is the Ampere (A)

Multiple Choice

__________________ is the continuous flow of electric charges through a material.

• Electric current
• Resistance
• Voltage
• Static Discharge

Multiple Choice

What is current measured in?

• Ω (Ohms)
• V (Volts)
• A (Amps)
• W (Watts)

Multiple Choice

Current is...

• moving protons
• moving electrons
• measured in volts
• measured in ohms

Multiple Choice

A complete, unbroken path that charges can flow through is called an __________________.

• conductor

• electric circuit

• electric current

• insulator

Multiple Choice

Metals such as copper and aluminum are good ______________. 

• insulators
• conductors
• circuits
• charges

Multiple Choice

______________ are materials such as rubber that do not allow charges to flow.

• conductors
• circuits
• insulators
• amps

Multiple Choice

Electric current is ___________

Multiple Choice

An electric current is _____________________

• the stopping of an electrically charged particle (electrons) in a conductor

• the flow of electrically charged particles (electrons) in a conductor

Electricity moves in currents

• Current is the flow of electrons from

  one place to another.

• Measured in amperes (amps)

• A form of kinetic energy

Multiple Choice

Electricity that moves is...

• potential energy

• kinetic energy

There are 2 Types of Electrical Current

• Direct Current (DC) – Where

  electrons flow in the same direction

  in a wire.

• Alternating Current (AC) –

  electrons flow in different

  directions in a wire.

Multiple Choice

There are how many types of electrical current?

• 4

• 2

• 3

• 6

Multiple Choice

In Direct Current (DC) ...

• Electrons flow in the SAME direction

• Electrons flow in DIFFERENT directions

Multiple Choice

In Alternating Current (AC) ...

• Electrons flow in the SAME direction

• Electrons flow in DIFFERENT directions

Multiple Choice

What are the two types of current?

• AC and DC

• CD and AC

• BC and AD

Multiple Choice

A wall outlet like in our house is an example of which type of current?

• AC

• DC

Multiple Choice

Identify which object using DC current.

• Stove

• Battery

• Television

Fill in the Blank

AC current can be converted to _____ current.

Fill in the Blank

DC current can be converted to _____ current.

Open Ended

Describe a device that might use AC current to charge a battery which is converted to DC current.

Fill in the Blank

Alternating current switches direction and ___ only travels in one direction.

What is current electricity?

an electrical charge in motion.

It consists of a flow of negatively charged electrons from atom to atom through a conductor in an electrical circuit.

The external force that causes the electron current flow of electric charge is called the electromotive force (emf) or voltage.

What are examples of current electricity?

Examples of current electricity are:

1) starting a car

2) turning on a light

3) cooking on an electric stove

4) watching TV

5) shaving with an electric razor

6) playing video games

7) charging a cell phone

What is Direct Current?

• Direct current (DC) is an electric current that is uni-directional, so the flow of charge is always in the same direction. 

• As opposed to alternating current, the direction and amperage of direct currents do not change. It is used in many household electronics and in all devices that use batteries

What are the uses of direct current?

• It is also used to:

• charge batteries, like laptops and cell phones

• They come with an AC adapter that converts alternating current to direct current

Multiple Choice

Electric current comes from the movement or flow of _____ charged electrons around an electric circuit.

• Proton

• Neutral

• Negatively

• Positively

Multiple Choice

What is an electric circuit?

• The path which the electric current takes.

• Movement or flow of negatively charged electrons

• A device to control the flow of electricity

• The current flow of electricity that always goes in one direction

Multiple Choice

The flow/movement of electric charges 

• Voltage
• Resistance 
• Current 
• Circuit 

Multiple Choice

Electric current that flows in only one direction. 

• Voltage 
• Direct Current 
• Alternating Current
• Series Circuit 

Multiple Choice

A material in which electrons are not able to move easily 

• Circuit 
• Insulator 
• Resistance 
• Conductor

Multiple Choice

A material in which electrons are able to move easily

• Circuit
• Insulator 
• Resistance 
• Conductor 

Multiple Choice

What is this in the picture?

• Plastic sticks

• Wires that carry electricity

• Skipping rope

Multiple Choice

A _____________ is a path that is made of parts that work together to allow current to flow.

• Static electricity

• Circuit

• Insulator

Multiple Choice

What type of electricity do we use everyday?

• Static electricity

• Electric current

Poll

Tick the ones you use everyday.

Multiple Select

Which two pictures show static electricity? Choose 2.

Multiple Choice

What is static electricity?

• It flows in a wire.

• It is a build up of electrical charge.

Multiple Select

Which two are the types of electrical charges? Choose 2 answers.

• Negative

• Right

• Positive

• Left

Multiple Choice

All electricity is the result of electrical charge.

• True

• False

Multiple Choice

What is an electric current?

• a build up of electrons

• the difference in charge between 2 points

• the flow of electrons over a circuit

• the opposition to flow of electrons

Multiple Choice

What is an electric current?

• a build up of electrons

• the difference in charge between 2 points

• the flow of electrons over a circuit

• the opposition to flow of electrons

What is a direct current?

• An electric current in which charges flow in one directly only.

• The current produces by electrochemical cells is direct current. The chemical energy is being changed into electrical energy.

• When the switch is on the electric current produced by the dry cells keeps the light bulb on

Alternating current:

• type of current that does not flow in one direction only.

• constantly changes direction at a regular rate.

• can be transported more easily over long distance

alternating current

alternating current can be changed to direct current. In the home, many electronic devices such as computers, televisions, sets, and CD players use direct current. Converters built into these devices converts alternating currents to direct currents.