Imagine a wheel rolling on the floor as shown in the picture. Let $P_{0}$ be a point on the circle wheel such that it's the point of contact between floor and wheel.
The book I am going through mentions that, the condition for rolling without slipping is , $$v_{\text{CM}}=Rw$$, Where $R$ is the radius of circle and $w$ is angular velocity.
My questions:-
$(1)$- Why is $v_{cm}=Rw$ the condition for rolling without slipping?
$(2)$- Why is it's said that $P_{0}$ is at rest. My argument is since the point is on the edge of wheel, shouldn't it move with the wheel?
