1. The problem statement, all variables and given/known data A horizontal rope pulls a 10kg wood sled across frictionless snow. A 5.0kg wood box rides on the sled. The coefficient of static friction for wood on wood is \mu_s=0.5. What is the largest tension force for which the box doesn't slip? 2. Relevant equations n=Fg=mg 3. The attempt at a solution So far I've got a picture and a free body diagram, with 3 total forces: Gravity defining down, normal force pointing up, and static friction pointed opposite the direction of motion. I tried setting T equal to static friction but I got the wrong answer. Can someone talk me through the problem so I know what I'm missing? Thanks.