| Question_Number,exam_name,subject,Category_Domain,Context,Question_Part_1,Question_Part_2,Question_Part_3,Table_1_Data,Image,Answer | |
| naep_sci_1,naep,science,physical_science,Explain the results of an investigation about conservation of energy,Compare the potential energy data and the kinetic energy data for each platform.,Describe the trend in the difference between the potential energy data and the kinetic energy data.,"Based on the law of conservation of energy, explain why that trend exists.","[ | |
| {""Platform from Which Ball is Dropped"": ""1"", ""Potential Energy at Platform (joules)"": ""3.0"", ""Kinetic Energy just above the Ground (joules)"": ""2.8""}, | |
| {""Platform from Which Ball is Dropped"": ""2"", ""Potential Energy at Platform (joules)"": ""6.0"", ""Kinetic Energy just above the Ground (joules)"": ""5.4""}, | |
| {""Platform from Which Ball is Dropped"": ""3"", ""Potential Energy at Platform (joules)"": ""9.0"", ""Kinetic Energy just above the Ground (joules)"": ""7.8""}, | |
| {""Platform from Which Ball is Dropped"": ""4"", ""Potential Energy at Platform (joules)"": ""12.0"", ""Kinetic Energy just above the Ground (joules)"": ""10.0""} | |
| ]",images/2019-12S7_4K1361E1_c9772f8a84fc11f249504ba264195d25_8_img.webp,"Student response is correct for Part 1, Part 2, and Part 3. | |
| Part 1: States that the initial potential energy (PE) is always greater than the kinetic energy (KE) just above the ground level. (The kinetic energy is always lower than the initial potential energy.) | |
| Non-acceptable response includes: both values increase. | |
| Part 2: States that the difference between the two energies becomes greater (increases) with increasing height. | |
| - Acceptable responses include: | |
| - The higher the platform the greater the difference in the KE and PE, and the higher the initial PE. | |
| - The PE always remains higher than the KE, growing farther apart as the platform height increases. | |
| - The higher the initial potential energy the larger the percentage of energy lost. | |
| - It keeps getting bigger. | |
| - The difference between PE and KE grows as the platform increases. | |
| - Non-acceptable responses include: | |
| - Definitions of KE and PE | |
| - The KE is about 85% of the PE- PE goes up by 3 each time | |
| Part 3: Explains that the difference in KE and PE is converted to thermal energy (lost as heat.) | |
| Alternate response may relate the difference to air resistance (friction). | |
| - Acceptable responses include: | |
| - With increasing height, the ball travels a longer time through the air, so more energy is transferred to thermal energy due to air resistance. | |
| - The longer the ball has to fall the more energy is transferred into thermal energy. | |
| - The farther the ball falls the more energy is lost due to friction. | |
| - As the platform becomes higher wind (air) resistance becomes more evident and has a greater effect on the ball. | |
| - As the ball falls, work is done on the ball by a nonconservative force. | |
| - Non-acceptable responses include: | |
| - More energy is conserved as the height increases | |
| - The ball conserves it for impact | |
| - The higher you drop the ball the more time it has to pick up speed | |
| - Energy is always conserved | |
| Note: Answer to one part may appear in another part. In such cases, the response is correct/incorrect and NOT blank." | |