1. The problem statement, all variables and given/known data A solid pulley wheel is rotated at a constant velocity for 10 sec's. Find the angular displacement? Wo (inital angular velocity) = 6Rad/s W (angular Velocity) = 0 Rads/s [itex]\alpha[/itex] = 0 (angular acceleration) Rads/s-2 θ = ? (angular displacement) Rads/s t = 10 sec 2. Relevant equations θ=Wo*t+1/2*[itex]\alpha[/itex]*t squared θ=(Wo+W)/2)*t 3. The attempt at a solution θ=Wo*t+1/2*[itex]\alpha[/itex]*(t squared) displacement θ = 6 * 10 + 1/2 * 0 * t = 60 Rads or θ=(6+0)/2)*10 = 30 Rads. I cannot tell which one is right as they both should find θ. All I know is that there is an angular acceleration of 0 and 60 is the right answer. Does this mean I have to use an equation with [itex]\alpha[/itex] in it? I thought I could use anyone I liked as it found θ. Another example is if I decelerate: Wo = 6 Rads [itex]\alpha[/itex] =-3Rads t = 2 sec θ=Wo*t+1/2*[itex]\alpha[/itex]*t squared displacement θ = 6 * 2 + 1/2 * -3 * (2^2) = 6 Rads or θ=(6+0)/2)*2 = 6 Rads. Why would this work out or is it just luck? I know the answer to be 6 Rads. Thank you for any help in advance.