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Magnetic field due to a long (straight) wire:. Let’s review:. current on ( I up ! ). Right hand rule (#1). ( I up/out ! ). DIRECTION-OK MAGNITUDE???. Experiment shows: For a long straight wire.
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Magnetic field due to a long (straight) wire: Let’s review:
( Iup/out !). DIRECTION-OK MAGNITUDE???
Experiment shows: For a long straight wire
Example: Suppose a cable is carrying 100 A current. What’s the B-field 1 cm from the cable? How about 10 cm?
Example: The cables are each carrying 25 A out the of page. What’s at point Q? 13.0 cm Q
Example: The cables are carrying 25 A out the of page. What’s at point P? 13.0 cm P 13.0 cm Individuals here, Total …..
Example: The cables are carrying 25 A out the of page. What’s at point P? P 13.0 cm 13.0 cm Individuals here, Total …..
Example: The cables are carrying 25 A out the of page. What’s at point P? 13.0 cm P 13.0 cm
Opposite Currents Repel!
Parallel Currents attract! (same magnitude as other case!)
Example: What force per unit length do two cables 1 cm apart produce on each other? (They’re carrying 50 A each.) How about at 10 cm?
Fun example: How much current do you need in the third wire so the net forces are zero?
Solenoids down/in Current Loop: up/out
Current LoopS: down/in up/out
Solenoid: down/in up/out
Example: What’s the B-field inside a coil with 50 turns/cm, running a current of 2 A?