Question

a science class is studying the motion of celestial bodies using models. each student assembles a model by tying a string to a rubber stopper, running the string through a straw, and tying the other end to a bundle of ten washers, as shown below. to model orbital motion, each student holds the straw above their head and moves the straw in a small circular motion. this causes the rubber stopper to revolve around the top of the straw. the weight of the washers pulls down on the string, and the string holds the stopper in a circular motion. what does the bundle of washers represent in the model? a. inertia b. weight c. mass d. gravity

Explanation:

In the model of orbital motion, the washers' weight pulls the string, representing the force that keeps the celestial body (rubber stopper) in orbit. Gravity is the force that attracts objects and keeps them in orbital motion (like planets around the sun). Inertia is resistance to motion change, weight is a force due to gravity on mass, and mass is the amount of matter. The washers here represent the gravitational force that provides the centripetal force for the circular motion of the stopper, so they model gravity.

Answer:

D. gravity