Final answer:
The size of the difference threshold is greater for heavier objects than for lighter ones, which is best illustrated by Weber's law.
Step-by-step explanation:
The size of the difference threshold is greater for heavier objects than for lighter ones. This phenomenon is best illustrated by Weber's law. According to Weber's law, the difference threshold is a constant proportion of the original stimulus, meaning that the larger the initial stimulus, the greater the difference needs to be for us to detect it.