2.14
2.14 24 November 2010 10:16
· 2.14 know that lamps and LEDs can be used to indicate the presence of a current in a circuit
> Crocodile technology
· Drag file 6 (attached) into the Croc clips window and it will open (you might have to save this file to your desktop first)
· Push the push switches on each of the 4 circuits
· Can you explain what you see? 2.14 answers 24 November 2010 10:16 Filament lamps
· Turn on when a current flows either way through them
· You can see that their V/I graph is symmetrical - they behave the same with positive and negative voltages [cid:image001.jpg@01CCD50B.40EAD4B0] Light Emitting Diodes (LEDs)
· Turn on when a current flows "forwards" through them (in the direction of the arrow)
· You can see that their V/I graph is asymmetric - they behave differently with positive and negative voltages
· Diodes are like a one way door that
o allows current to flow when a positive voltage is applied
o does not allow current to flow when a negative voltage is applied [cid:image002.png@01CCD50B.40EAD4B0]
· 2.14 know that lamps and LEDs can be used to indicate the presence of a current in a circuit
> Crocodile technology
· Drag file 6 (attached) into the Croc clips window and it will open (you might have to save this file to your desktop first)
· Push the push switches on each of the 4 circuits
· Can you explain what you see? 2.14 answers 24 November 2010 10:16 Filament lamps
· Turn on when a current flows either way through them
· You can see that their V/I graph is symmetrical - they behave the same with positive and negative voltages [cid:image001.jpg@01CCD50B.40EAD4B0] Light Emitting Diodes (LEDs)
· Turn on when a current flows "forwards" through them (in the direction of the arrow)
· You can see that their V/I graph is asymmetric - they behave differently with positive and negative voltages
· Diodes are like a one way door that
o allows current to flow when a positive voltage is applied
o does not allow current to flow when a negative voltage is applied [cid:image002.png@01CCD50B.40EAD4B0]

