1. The problem statement, all variables and given/known data Lets say I have a ball rolling on a flat frictionless surface. I give it an impulse to set it into rolling without slipping at a speed u. The mass of the ball is m and the radius is a. How large is the impulse and where is it applied 2. Relevant equations I guess linear and angular momentumn 3. The attempt at a solution Well i know linear impulse is the change in linear momentum and for angular impulse it is the change in angular momentum. However, I am confused about what impulse is. Is it the addition of linear and angular impulse? Moreover, I think this question will have a range of answers since i doubt it is only one spot where I will apply the impulse and get rolling without slipping but I am just confused.