Connecting the crank and slider is the connecting rod (2) which moves in general plane motion, which is a combination of pure rotation and pure translation. Therefore, its angular velocity (ωrod) and angular acceleration (αrod) will vary, depending on the relative lengths of the crank (1) and connecting rod (2) and the given magnitude and direction (clockwise or counterclockwise) of the angular velocity (ωcrank) and angular acceleration (αcrank) of the crank.