Recent content by alphaJA

ohh I see. then do I have to make it vf=vi- mu_k*g*t?? If so, how can I make it just negative? or is there something else that I'm still missing.

isnt g=-9.8m/s^2? so doesn't the velocity decrease with time? or is that not true with the equation vf= vi + mu_k*g*t..? Thanks a lot for assisting me, by the way.

equations describing the velocities... do you mean things like Vf=Vi+at, omega_f= alpha*t? alpha = (mu*g)/(0.4R) using torque... and omega_f = Vf/R because it is not slpping at the point... so omega_f/alpha= time? if that's right.. i got time = (0.4V_f)/(mu_k*g)... I still need to know how to...

eventually omega=v/R...(am I missing the point?Im not sure) when it is not slipping... well for a) it only need the function when it is rolling with slipping.. if omega=0, and is slipping, does it mean it is sliding? Is it at a certain distinct point that it will start not slipping, or is it...

hmmmm it says slipping on the paper... anyway...I'm still stuck on this problem..

I thought that alpha= a/r does not work when it is slipping... if its slipping, then it might be spinning like crazy, but still not be accellerating much horizontally.

Homework Statement A billiard ball has mass M, radius R, and moment of inertia about the center of mass(sphere...so (2/5)MR^2). The ball is sturck by a cue stick along a horizonal line through the ball's center of mass so that the ball initially slides with velocity vi. As the ball moves...