How can I create a scroll up button on some survey pages?

Hello,
I created a survey with a footnote at the bottom of most pages. The footnote does not use the Footer option, but is a question at the end of the page. I set it up like this because I added a link at the top of the page and a text anchor at the bottom for the definition (using a simple code with Javascript). The problem with adding the footnote at the bottom, the participant will need to scroll up a somewhat lengthy page (I'm trying to keep the survey to 2 pages). I want the participant to be able to click the button and have it take them to the top. I believe this can be done through javascript, but I've only recently starting exploring it and I'm not sure what I'm doing. Does anyone know how to do this?
Thanks!