Yes of course there is ! If you can verbalize this concept, many others have also thought it and several have made one. I would be happy to enlighten you after you perform your solemn duty and assign best answers to those who responded with answers to your previous 12 or so inquires into self education. Do let me know here :-)
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Yes, its called a relay.
I have a relay but it is activated when 5v is applied across it BUT i want to activate it when there is no current flowing 0v across it
And what happens on the contacts ?????? You have a normally "open" contact, and a normally closed one. Use the normally closed contact to switch your circuit. When the coil is ON your second circuit it OFF, as you asked.