In a chain drive system, the speed and torque of the driven shaft are determined by the __________.

In a chain drive system, the speed and torque of the driven shaft are directly influenced by the relative number of teeth between the driven sprocket and the drive sprocket. The relationship of the number of teeth determines how the power is transmitted from one sprocket to another. When the driver sprocket has a different number of teeth than the driven sprocket, it creates a mechanical advantage that affects both torque and speed.

When the driven sprocket has fewer teeth than the driver sprocket, for instance, the driven shaft will rotate faster, but with less torque. Conversely, if the driven sprocket has more teeth, it will rotate slower while producing greater torque. This principle is fundamental in designing mechanical systems that require specific speed and torque outputs, as it allows engineers to tailor the drive system according to the needs of the application.

The other options provided do not accurately capture how these factors interact in a chain drive system. The pitch circles and diameters can provide useful insights into the mechanics of the sprockets, but they are ultimately derived from the number of teeth, making the teeth count the primary driver in determining speed and torque ratios.