i brought my first electric today.im pretty well established on acoustic but when i came to play my electric .i decided to have a mess around with the tremelo bar.i notice that when i push down on it it lifts the bridge of the guitar off the guitar surface. is this normal ?
Which model of electric guitar do you have? Tremolos can work in different ways on different models. It is probably normal, basically the tremolo bar usually moves the part where the strings are fastened on the body end of the guitar. This lengthens or shortens them causing a change in pitch
...and depending on whether it's a decent make or not may well cause the guitar to go out of tune every time you use it (used to have a beautiful Marlin guitar - drove me nuts)