Science Assessment ~ Items ~ NG009006

A boy holds a book above the floor. He lets go of the book and the book speeds up as it falls to the floor. Which of the following describes the changes in energy that take place while the book is falling? Explain.

As the book is falling, gravitational potential energy decreases, and kinetic energy (motion energy) increases because gravitational potential energy is transformed into kinetic energy.
As the book is falling, gravitational potential energy decreases, but kinetic energy (motion energy) does not change, so no energy transformation takes place.
As the book is falling, kinetic energy (motion energy) increases, but gravitational potential energy does not change, so no energy transformation takes place.
As the book is falling, neither gravitational potential energy nor kinetic energy (motion energy) changes, so no energy transformation takes place.

Details
Performance
NGSS

Topic: Energy: Forms, Transformation, Transfer, and Conservation
Correct Answer: A

Distribution of Responses

Chart showing distrubtion of responses for Item EG009006

Scale Score for Item Difficulty (200[Easy]-800[Difficult]): 490

Students Responding Correctly

Group	Correct	Total	Percent
Overall	574	1158	50%
Grades
4–5	N/A	N/A	N/A
6–8	256	602	43%
9–12	318	556	57%
Gender
Male	278	578	48%
Female	284	552	51%
Primary Language
English	516	1019	51%
Other	46	108	43%

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 NG009006: Both gravitational potential energy and motion energy are involved in an energy transformation when a book falls. As the book is falling, its gravitational potential energy decreases and its motion energy increases.