Science Assessment ~ Items ~ NG014003

A rubber ball speeds up as it falls toward the floor. How and why do the kinetic energy (motion energy) and gravitational potential energy of the ball change as it falls?

The gravitational potential energy stays the same and the kinetic energy increases because as an object speeds up, new energy in the form of kinetic energy is made.
The kinetic energy stays the same and the gravitational potential energy decreases because as an object speeds up, gravitational potential energy is used up and is not converted into any other form of energy.
The kinetic energy decreases, and the gravitational potential energy increases because the kinetic energy is converted into gravitational potential energy.
The kinetic energy increases, and the gravitational potential energy decreases because the gravitational potential energy is converted into kinetic energy.

Details
Performance
NGSS

Topic
Correct Answer: D
Misconceptions

Distribution of Responses

Chart showing distrubtion of responses for Item 014003

Scale Score for Item Difficulty (200[Easy]-800[Difficult]): 522

Students Responding Correctly

Group	Correct	Total	Percent
Overall	306	976	31%
Grades
4–5	N/A	N/A	N/A
6–8	185	629	29%
9–12	121	347	35%
Gender
Male	136	443	31%
Female	159	505	31%
Primary Language
English	267	853	31%
Other	30	99	30%

View data table

NRC Framework: PS3.A …lifting an object increases the stored energy in the gravitational field between that object and Earth (gravitational potential energy) compared to that for the object at Earth’s surface; when the object falls, the stored energy decreases and the object’s kinetic energy increases.

Science Assessment

Item NG014003: As a rubber balls falls to the floor, the motion energy of the ball increases and the gravitational potential energy of the ball decreases because the gravitational potential energy is transformed into motion energy.