Here comes the real issue, to calculate energy, we must square voltage to get power, and add up power values multiplied by how long each power value lasted for (energy=timestep*SUM(powers)). We are dealing with the error of the oscilloscope's time resolution. To get the final uncertainty we must add up the relative uncertainties of the timestep and uncertainty of the sum of powers. If I am to say that the error in the time resolution is ±4 microseconds, then I necessarily must have a relative error of at least 4μs/8μs=0.5 which is tremendous. That does not seem right, so which method of estimating uncertainty is correct here?

Thank you all