Question

a student attaches a rope to the handle of a chest loaded with a few books, while the other end of the rope is tied to a spring scale. the student pulls the scale with just enough force to set the chest in motion and records the force applied on the spring scale. the student repeats the experiment with more books in the chest and records the data in a table. what can be concluded from the data? as the mass of the chest increases, less force is required to pull it. as the mass of the chest increases, more force is required to pull it. the amount of frictional force increases as the mass of the chest decreases. the amount of frictional force decreases as the mass of the chest increases.

Explanation:

As we look at the table, when the mass of the chest (number of books) increases from 50 kg to 175 kg, the force required to set the chest in motion increases from 0.25 N to 1.70 N. Friction force is what the student is overcoming to set the chest in motion, and it is directly related to the normal force which is proportional to the mass (on a horizontal surface, normal force $N = mg$). So, more mass means more normal force and more friction force to overcome.

Answer:

As the mass of the chest increases, more force is required to pull it.