When Two Variables in a Graph Are Related to a Third

question 1

Multiple Choice

When two variables in a graph are related to a third, changing the third causes

• A) either a shift or a movement in the curve but more information is needed to determine which occurs.
• B) a movement along the curve.
• C) no change in the curve because the third variable isn't on the axes.
• D) a shift of the curve.
• E) None of the above answers is correct.

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Definitions:

Sensory Input

The stimulation that is received by the sensory receptors, leading to sensations and perceptions, originating from the external or internal environment.

Psychophysicist

A scientist who studies psychophysics, a discipline focusing on the relationship between physical stimuli and the sensory responses these stimuli evoke in the human mind.

Difference Threshold

The minimal difference in intensity required between two sources of energy so that they will be perceived as being different.

Ernst Weber

A pioneering psychologist known for his work in the area of the sense of touch and the Weber-Fechner law regarding the perception of changes in a stimulus.