Final answer:
Just-Noticeable Difference (JND), or difference threshold, is the smallest detectable change in a stimulus, as defined by Weber's Law. The JND is proportional to the original stimulus's magnitude. In sensory experiments, weights are often increased by specific percentages to test this concept.
Step-by-step explanation:
The term Just-Noticeable Difference (JND), also known as the difference threshold, refers to the minimum amount of change in a sensory stimulus needed to be noticeable at least 50% of the time by the observer. Weber's Law proposes that the JND is proportional to the magnitude of the original stimulus. This concept is crucial in various fields, including psychology and sensory science, where it helps in understanding human perception.
When conducting an experiment to test JND for weights, one might use a start weight of one pound and increase the weight by either 10% or 20% at each step. If the observer can detect the difference between the weights when incremented by these percentages, the results would potentially support Weber's Law. However, if the observer cannot consistently detect the increments as anticipated, then there might be other factors influencing the perception of weight changes.