dc powerjack 13 7000 inspiron

so my dc power jack has been unplugged from the motherboard. I am not familiar with software and technology so excuse my language. From what I understand, the white part is supposed to be "plugged in" to a socket, which has the reciprecal contents (power source?) but when I do that, I am not sure why it is still lose. Would it be easier to send it in for service? or cut the wires for the jack (meaning it could be a different problem?) I would appretiate any advice.