If an electric wire is allowed to produce a magnetic field no larger than that of the earth (0.55 x 10-4 t) at a distance of 25 cm, what is the maximum current the wire can carry?

State one advantage and one disadvantage of using a plane mirrior as a driving mirrior

1. a camcorder has a power rating of 19 watts. if the output voltage from its battery is 7 volts, what current does it use?answer units 2. a 1.5m wire carries a 6 a current when a potential difference of 57 v is applied. what is the resistance of the wire? yourunits 3. a clothes dryer uses about 2 amps of current from a 240 volt line. how much power does it use? yourunits 4.

Explain why electric current cannot exist if a current doesn't have a voltage source.