1. The problem statement, all variables and given/known data How do you solve this?? A 2kg block starts from rest slides down a friction-less incline plane that is at angle of 20degree with the horizontal. At a certain point on the incline, the speed of the block is 9m/s. 1.What is the vertical distance the block has traveled?? 2.What is the work done by gravity as the block moves the vertical distance you found?? 2. Relevant equations Work= Force x Displacement KE= .5mv^2 PE= mgh 3. The attempt at a solution for number 1, I know that my PEf nd KEi =0. So i set PEi and KEf equal to each other. PEi=KEf. So what i did was mgh=.5*m*v^2. m's cancel out. so 9.8h=.5v^2. .. This is where i am stuck.. I am not sure if i am doing right.. But how do i find v which is velocity?