Question

Which of the following is an example of how a scientist might use a model?

A. Marbles placed inside a hollow sphere are used to describe protons in a nucleus
B. A wrench is used to tighten a nut onto a piece of wood
C. Stopwatches measure the amount of time it takes for runners to complete a mile
D. Microscopes are used to magnify a group of cells on sets of slides

Answer 1

The correct option would be

A: Marbles placed inside a hollow sphere are used to describe protons in a nucleus.

Answer 2

The correct option is A.
In science, model refers to a representation of idea, object or process which is used to describe a phenomenon that can not be directly observed.
In option A, it can be seen that protons that are inside the nucleus of an atom can not be seen with the naked eyes, that is why scientists used models to represent them.