I found a similar problem online at http://216.239.39.104/search?q=cache:PRmIS-JQPBMJ:www.mente.elac.org/faculty/kiledjianv/phys%2520001/ec.pdf+%22large,+cylindrical+roll%22+tissue+paper&hl=en&ie=UTF-8 and they got the answer.
OK here's a question which I really, really can't understand.
A large, cylindrical roll of tissue paper of initial radius R lies on a long, horizontal surface with the outside end of the paper nailed to the surface. The roll is given a slight shove (initial velocity is about zero) and...
This UTexas thing is at hw.utexas.edu. It's an online program that my physics teacher uses to torture us. Doc Al, the program specifically says "Enter what your calculator says" and it allows a 1% error anyways so I'm pretty sure that's not the problem.
A 8.63 kg box slides down a long, frictionless incline of angle 20 degrees. It starts from rest at time t = 0 at the top of the incline a height 24.6 m above ground.
Find the potential and kinetic energy of the box at t = 1.8s. Answer in units of J.
acceleration is gsin20
so I got velocity...