1. The problem statement, all variables and given/known data Suppose a slide is 35.0 meters high, but is a straight slope, inclined at 45 degrees with respect to the horizontal. a) find the speed of a 60.0kg thrill seeker at the bottom of the slide, assuming no friction. b) if the thrill seeker has a speed of 20.0m/s at the bottom, find the change in mechanical energy due to friction c) find the magnitude of the force of friction 2. Relevant equations KEi + PEi = KEf + PEf 3. The attempt at a solution a) since there is no friction, mechanical energy is conserved. So therefore using the above equation: KEi + PEi = KEf + PEf. However, i have difficulty when the question adds an angle. When do I know when to break into x and y components?? In this case, KEi = 0, PEi = mgy1, KEf = 1/2mv^2, PEf = 0 Therefore, PEi = KEf mgy1 = 1/2mv2^2 square root of 2gy1 = v2^2 (where y1 = 35m) is that right?