To view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 video Your turn! Get busy videoing your answer or challenge, then send it through to us below - maybe you can teach us a thing or two! Upload Watch more videos Replay video Add to favourites Remove from favourites Add to your favourites 7 4 4 All wired up, with Nora Carrot By Nora Carrot 1 person 15 mins Ever wondered why wires have positive and negative ends? Does that mean one side is happy and one is sad? Help Nora Carrot suss this out! Electronic Engineering Science & Engineering Nora Carrot