1. A solid uniform cylinder of mass M and Radius is projected up an incline of angle Ө. It rolls without slipping from an initial speed V๐ of the center of mass. What distance s does the center of cylinder travel before it starts to fall back? 2. I=½MR², V²=V๐²+2as, F=ma, a=R²α ... 3. MgsinӨ+f=ma=mR²α , f=Iα/R 0²=V๐²-2as , I=I=½MR² , a=2gsinӨ s=V๐²/4gsinӨ -------- But the answer page of the book says s= (3V๐²/4g) sinӨ [exactly as it's written---Prob. 9/67 PHYSICS for.... 3rd Edition; Fishbane-Gasiorowich-Thornton] --------- I've found another solution from another book which goes with the conservation of the energy: ½MV๐²+½Iω๐²=MgH , H=SsinӨ For a solid uniform cylinder, rotational kinetic energy is 1/3th of total energy and therefore: 3/2(½MV๐²)=MgSsinӨ, s=3V๐²/4gsinӨ Which of us is correct????