1. The problem statement, all variables and given/known data A drum of radius R rolls down a slope without slipping. Its axis has acceleration "a" parallel to the slope. What is the drum's angular acceleration A? 2. Relevant equations x(t) = x_0 + v_0 + 1/2gt^2 (because of constant acceleration) w = S / 2pi 3. The attempt at a solution The center of the circle moves according the kinematic equation for position with constant acceleration. If we consider its starting position as 0, then the position just gives the distance traveled by the center. I hope that I can also say that the initial velocity is 0 (can I?) So then the distance traveled is 1/2gt^2. Dividing by 2R * pi gets us the number of revolutions, and then multiplying by 2pi gives the number of radians. so (1/2R)gt^2 after simplification. If we divide by time, we should get w, or the angular velocity as gt/(2R). Upon taking the derivative to find the angular acceleration, I get g/(2R). But this definitely does not seem right.