What effect does placing the belt on the smaller sheave have on drill speed?

Placing the belt on the smaller sheave increases drill speed due to the mechanics of pulley systems. When a drive belt is placed on a smaller sheave, it effectively alters the ratio between the driving pulley and the driven pulley. The smaller the sheave on which the belt is placed, the higher the rotational speed that is transmitted to the drill.

This happens because the circumference of the smaller sheave is less than that of a larger one, resulting in more rotations of the smaller sheave for each rotation of the larger one. As a result, the output speed increases when using the smaller sheave. Higher speeds can be beneficial for tasks that require more precise drilling or faster operation in general.

In contrast, the other options either reflect a misunderstanding of pulleys and mechanics or the principles governing torque and speed dynamics. The unchanged speed would imply no change in rotational dynamics, which is unfounded in this setup. Torque might be modified, but the primary effect in this case concerns the increase in speed rather than a mere effect on torque alone.