1. The problem statement, all variables and given/known data An adventurous camper (71 kg) finds him/her self stranded in the middle of a frozen lake (diameter = 1.3 km) with only a bag of rocks (total mass 10.0 kg). The ice is so slippery, that they move about the lake's surface without friction (don't ask me how they got there in the first place). Remembering what they learned in a physics lab, they devise a way to get themselves to the edge of the lake by throwing the bag of rocks in the opposite direction of the shore with a velocity of 6.0 m/s. If they throw the rocks all at once, how long does it take for them to slide to shore? 2. Relevant equations The topic of the lab was elastic and inelastic collisions, however this problem doesn't really have to do with the other questions. Sum of Fx=ma 3. The attempt at a solution Since it's on a friction-less surface, I know that the sum of the forces in the x direction is equal to ma, and that the velocity is what causes the camper and his rocks to keep moving, however I don't know where to go from there. I've tried using some of the kinematics formulas to try to solve for t, but I can't seem to get it right.