As far as I can see, there are only two basic types of motor where the question would be relevant; stepper motors (most likely), which are designed to be pulse driven , or DC motors which are designed to be run on a constant DC, but could be driven by a suitable pulsed supply.
The whole point of stepper motors is that they move one step for each pulse (#), so you can control exactly how much and how fast they turn (within limits.) And that tells you what you need to answer the question.
(#Half stepping and other complications ignored for now.)
The pulse amplitude and duration affect the current, and thus the magnetic field, which affects the torque. Too little torque and the step does not happen, but extra torque does not move more steps.
If you *were* looking at a DC motor driven by a pulsed supply, you use an averaging process.
If the pulses are widely spaced, you can simply regard the motor as being repeatedly switched on and off. The changes to the pulses will do what you'd expect if you did the same with your DC supply (amplitude would be DC Voltage.)
When the pulses are closer together (many pulses per revolution) you can look at your your pulse train and work out the average DC equivalent. Any changes to the pulses will change this DC average and affect the motor accordingly.