Which of the following statements about physical models is not true?
a. physical models are often three-dimensional representations.
b. physical models are used to represent an object or event.
c. physical models are usually in the form of a graph.
d. physical models can be used to depict microscopic objects.

Option (c) is the correct answer.

Explanation:

A physical model is the representation of an object in order to tell or show the kind of structure, bonding or orientation of the object.

Characteristics of physical models are as follows.

Thus, we can conclude that the statement physical models are usually in the form of a graph is not true about physical models.