R1, no outs. Ground ball to F5 who throws to F4 at second for the force out. The throw is too late and R1 collides with F4. R1 does not slide.
See the video here: http://mlb.mlb.com/video/play.jsp?content_id=13446945
This is a great video because it highlights the differences between the OBR rule and the force play slide rules in NFHS and NCAA. Under OBR, R1 did nothing wrong and is safe at 2B. Under NFHS and NCAA, R1 and the B/R are both out (double play) as a result of R1's failing to slide or avoid contact on a force play at 2B.