1. The problem statement, all variables and given/known data A 4.1 kg block starts at rest and slides a distance d down a frictionless 26.0 deg incline, where it runs into a spring. The block slides an additional 18.0 cm before it is brought to rest momentarily by compressing the spring, whose spring constant is 428 N/m . [URL]http://loncapa4.fsu.edu/enc/64/444d8fc39f68b5d50a0ae69506afa18b07b17f4630544f446b909dc06ad62e4ccad64d37e395dbf1b8bce7f718c3ca893e7291ecae8bce02527ece77d5a672e050dafc3a7d01eb0880c83b19b1ecf1e46bc159a279e62c69.gif[/URL] What is the value of d?..(answered) What is the distance between the point of first contact and the point where the block's speed is greatest?.....(need help) 2. Relevant equations U = mgh U = .5k(x^2) 3. The attempt at a solution I found the answer to the first question by using the above relevant equations: U = mgh = .5k(x^2) 4.1 * 9.81 * h = .5 * 428 * (.18^2) h = 0.172 m then some trig.. sin(26)=.172/(.18 + d) d = .213 m As far as how to solve the second question I am completely lost. At the point of contact with the spring the acceleration should be zero correct. From there would I need to find the intial velocity? We know that V_f = 0, but how to use these "known" quantities in relationship to the block being slowed by the spring is confusing me. I think I'm making this problem more complicated than it realy is. TIA for your help.