How to call another function on slider handle change?

How to call another function on slider handle change?

I am pretty new to jQuery.
I have got the slider working and I am trying to create a volume
control.
I have got the control so far that I have a function which takes a
value and changes the volume.
Now I need to find a way to call that function when the handle of the
slider changes, passing the value of the handle.
<script>
    $(function(){
        // Slider
        $('#slider').slider({
             orientation: 'horizontal', step: 5, value: 50, animate: true
        });
    });
</script>
Tha'ts how far I have got. The function call is for example:
"changeVolume(number 1-100);"
Any help very much appreciated.
Thanks
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