MEGA
Energy Changes
A decrease in energy in one object or set of objects always is accompanied by an increase in energy in another o…
Item EC066001: When a child releases an elastic band in a slingshot to shoot a stone, the energy of the stone increases, and the energy of the elastic band decreases.
A slingshot (pictured on the right below) is a device made of a rigid frame and a strong elastic band. A slingshot can be used to propel small objects such as stones or balls. When the elastic band is pulled back and then released, the stone or ball will fly toward the target (pictured on the left below).
A child places a small stone in a slingshot and pulls the elastic band back. When the elastic band is released, what happens to the energy of the stone and the energy of the elastic band?
- The energy of the stone increases, and the energy of the elastic band increases.
- The energy of the stone increases, and the energy of the elastic band decreases.
- The energy of the stone increases, and the energy of the elastic band stays the same.
- The energy of the stone stays the same, and the energy of the elastic band decreases.
Pre-Test
Answer Choice |
Overall |
Grades |
Gender |
Primary Language |
||||
|---|---|---|---|---|---|---|---|---|
| n = 242 |
6–8 n = 0 |
9–12 n = 221 |
Male n = 133 |
Female n = 80 |
English n = 210 |
Other n = 13 |
||
| A. | The energy of the stone increases, and the energy of the elastic band increases. | 33% | NAN% | 33% | 30% | 39% | 33% | 31% |
| B. | The energy of the stone increases, and the energy of the elastic band decreases. | 37% | NAN% | 37% | 41% | 34% | 37% | 46% |
| C. | The energy of the stone increases, and the energy of the elastic band stays the same. | 17% | NAN% | 16% | 17% | 14% | 17% | 8% |
| D. | The energy of the stone stays the same, and the energy of the elastic band decreases. | 13% | NAN% | 13% | 12% | 14% | 13% | 15% |
Post-Test
Answer Choice |
Overall |
Grades |
Gender |
Primary Language |
||||
|---|---|---|---|---|---|---|---|---|
| n = 288 |
6–8 n = 0 |
9–12 n = 261 |
Male n = 158 |
Female n = 95 |
English n = 241 |
Other n = 15 |
||
| A. | The energy of the stone increases, and the energy of the elastic band increases. | 22% | NAN% | 23% | 25% | 19% | 24% | 7% |
| B. | The energy of the stone increases, and the energy of the elastic band decreases. | 64% | NAN% | 64% | 58% | 73% | 63% | 80% |
| C. | The energy of the stone increases, and the energy of the elastic band stays the same. | 7% | NAN% | 8% | 8% | 6% | 7% | 7% |
| D. | The energy of the stone stays the same, and the energy of the elastic band decreases. | 7% | NAN% | 6% | 9% | 2% | 6% | 7% |