How can horsepower be calculated for a motor nameplate without using wattage?

Horsepower can indeed be calculated using torque and RPM, and the formula provided is a commonly accepted method for doing so. The equation HP = (Torque * RPM) / (5,252) effectively relates these three variables.

In this formula, torque is measured in pound-feet (lb-ft) and RPM is the motor's revolutions per minute. The constant 5,252 is derived from the conversion factors used to relate torque and rotational speed to horsepower. Specifically, it combines units of measurement to ensure the left side represents horsepower.

By substituting the correct values for torque and RPM into this equation, you derive an accurate representation of the motor's horsepower. This formula is particularly useful in practical applications where the nameplate data for a motor does not provide wattage, allowing technicians to easily calculate horsepower using readily available torque and RPM values.

The other options do not accurately reflect the relationship between torque, RPM, and horsepower, either misapplying the formula or incorrectly organizing the variables.