1. Current electricity

2. elephantnose fish – 500 electric sensors to help find food at night
electric eel – thousands of muscle cells in tail that work like little batteries
electricity bursts up to 5X that of a wall socket
stun prey and attract mate
Pacific electric ray – electric organ in head
generate enough electricity to knock down a human

3. Learning goals We are learning to understand current electricity.
We are learning to examine the components and makeup of circuits.

4. Continuous flow of electrons
two conditions needed:
an energy source
a complete path to flow through (electrical circuit)
current electricity: continuous flow of electrons in a circuit

5. Try this
complete marble activity

6. Electric circuits
electrical load: device that converts electrical energy to another form of energy
heaters, lamps, light bulb, computer hard drive
switch: device that turns the circuit on/off by closing/opening
switch closed = circuit complete and electrons flow
switch open = break in path; no flow

7. Electric circuits wire: provides a path for the electrons to flow
insulator and conductor
source: provides the electrons
battery

8. Electrochemical cells
package of chemicals that converts chemical energy into electrical energy that is stored in charged particles
battery
electrolyte: liquid or paste that conducts electricity
contains chemicals that form ions
electrode: metal strips that react with electrolytes
zinc and copper used in a battery

9. Electrochemical cell

10. Electrochemical cell wet cell: liquid electrolyte
cars and other motorized vehicles
dry cell: paste instead of liquid electrolyte
flashlights, hand-held video game devices, cameras, watches
electrodes called terminals – end points where we make a connection

11. Recycling and recharging
recycle
contain toxic chemicals
rechargeable dry cells – used many times
less impact on environment

12. Fuel cells
generates electricity directly from a chemical reaction with a fuel
e.g., hydrogen
electric vehicles

13. Forms of current electricity
current electricity can be produced directly or it can be generated in a generating station
direct current (DC): a flow of electrons in one direction through an electric circuit
battery
alternating current (AC): a flow of electrons that alternates in direction in an electric circuit
wall outlets

14. Please complete
How is current electricity different from static electricity?
What is an electric circuit?
List three components of an electric circuit.
What is the difference between an electrolyte and an electrode?
Why should dry cells be recycled rather than thrown in the trash?

15. Learning goals We are learning to understand current electricity.
We are learning to examine the components and makeup of circuits.

16. Please complete