what would my cron path look like?

Hi All,
I 've been trying to add a cron job to call a php file without much success.

the problem (I think) is with the path but nowhare can I find specific help that works for me.

my cron job: * * * * * /usr/bin/php -f /home/mydomain/public_html/myfolder/myscript.php?key=val

The server is lightspeed & siteworx/nodeworx

I get a cron email reponse saying: Could not open input file: /home/mydomain/public_html/myfolder/myscript.php?key=val

any help is gratefully welcomed

jn

(all paths/names have been changed to protect the innocent)