Science Assessment ~ Items ~ NG005004

A boy holds a piece of clay above the floor. After he drops the clay, it speeds up as it falls. As it hits the floor, the clay flattens and gets a little warmer.

Which of the following describes the changes in the energy of the clay ball?

As the clay falls, its gravitational potential energy is converted to kinetic energy (motion energy). As it hits the floor, its kinetic energy is converted to thermal energy.
As the clay falls, its kinetic energy (motion energy) is converted to gravitational potential energy. As it hits the floor, its gravitational potential energy is converted to thermal energy.
As the clay falls, its gravitational potential energy is converted to kinetic energy (motion energy). As it hits the floor, its kinetic energy is used up but is not converted into thermal energy.
As the clay falls, its kinetic energy (motion energy) is converted to gravitational potential energy. As it hits the floor, its gravitational potential energy remains the same and is not converted into thermal energy.

Details
Performance
NGSS

Topic
Correct Answer: A
Misconceptions

Distribution of Responses

Chart showing distrubtion of responses for Item 005004

Scale Score for Item Difficulty (200[Easy]-800[Difficult]): 493

Students Responding Correctly

Group	Correct	Total	Percent
Overall	824	1771	47%
Grades
4–5	169	405	42%
6–8	378	800	47%
9–12	277	566	49%
Gender
Male	397	816	49%
Female	407	916	44%
Primary Language
English	756	1605	47%
Other	47	127	37%

View data table

Disciplinary Core Ideas: PS3.B When the motion energy of an object changes, there is inevitably some other change in energy at the same time.
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.; PS3.B For example, the friction that causes a moving object to stop also results in an increase in the thermal energy in both surfaces…

Science Assessment

Item NG005004: As a piece of clay falls, its gravitational potential energy is converted to motion energy, and as it hits the floor its motion energy is converted into thermal energy.