Powerpoint Help

OK, I'm working on a powerpoint slide show for a family event (a slide show of pictures for my grandma) and I am trying to program it so it will switch the slides on a consistant time interval. For example, when I hit start the slide show-I want the first slide to be visible for 5 seconds and then it switch to the next slide (which again will be visible for 5 seconds). Is it possible to set up a powerpoint slide show so it will be totally automated once you start it and so it switches slides on a time interval. This is a very simple slide show, there are no animations at all. All there is is one photo per slide. So, I just need it to automatically change a slide every 5 seconds. I'm sure thats possible, but I have no idea how to do it (other than manually changing the slide with the mouse every 5 seconds and I can't do that).