7. In an investigation of energy transfer, a student observes a roller coaster at locations A, B, C, and D. Then she creates the graph below of the roller coaster’s potential and kinetic energy at each location.
Which statement is true according to the graph?
(1 point)
Responses
Potential energy increases, but kinetic energy does not change.
Potential energy increases, but kinetic energy does not change.
The roller coaster creates kinetic energy.
The roller coaster creates kinetic energy.
The roller coaster destroys potential energy.
The roller coaster destroys potential energy.
The roller coaster’s kinetic and potential energy change from location to the next, but its total energy remains the same.
The statement "The roller coaster’s kinetic and potential energy change from location to the next, but its total energy remains the same" is true according to the graph.
9. Rebecca climbs the ladder of a large water slide, waits her turn at the top, and then slides down the slide into a pool. Which answer best describes the energy changes during her time on the slide?(1 point)
Responses
potential → kinetic → potential
potential → kinetic → potential
kinetic → mechanical → potential
kinetic → mechanical → potential
potential → mechanical → kinetic
potential → mechanical → kinetic
kinetic → potential → kinetic
The best answer is "potential → kinetic → potential".
8. The pendulum in the diagram below swings from position A to B.
If we don’t consider friction, what happens to the total mechanical energy as the pendulum swings from position A to position B?
(1 point)
Responses
It becomes greater.
It becomes greater.
It remains the same
It remains the same
It declines
It declines
It is not conserved
The total mechanical energy remains the same as the pendulum swings from position A to position B.
14. As energy is transferred or conserved, some of that energy becomes unavailable to do work. What happens to this unavailable energy?(1 point)
Responses
The unavailable energy is given off as microwaves
The unavailable energy is given off as microwaves
The unavailable energy is destroyed
The unavailable energy is destroyed
The unavailable energy is given off as heat
The unavailable energy is given off as heat
The unavailable energy is conducted
The unavailable energy is given off as heat.
16. An aluminum block has a starting temperature of 300oC. The block is placed into 200 milliliters of water, which has a temperature of 20oC. What heat transfer will occur?(1 point)
Responses
Heat will flow from the block to the water until both substances have the same temperature as their container.
Heat will flow from the block to the water until both substances have the same temperature as their container.
Heat will flow from the block to the water until both substances have a temperature of 20 degrees Celcius.
Heat will flow from the block to the water until both substances have a temperature of 20 degrees Celcius.
Heat will flow from the block to the water until both substances have a temperature between 20 degrees Celsius and 300 degrees Celcius.
Heat will flow from the block to the water until both substances have a temperature between 20 degrees Celsius and 300 degrees Celcius.
Heat will flow from the block to the water until both have a temperature of 300oC.
Heat will flow from the block to the water until both substances have the same temperature as their container.
17. Two samples of pure water are mixed with food coloring. One sample is red, and the other is blue. When the two water samples are combined, the red water floats on top of the blue water. Which statement best explains this result? (1 point)
Responses
The blue water is warmer and is more dense.
The blue water is warmer and is more dense.
The red water is colder and is more dense.
The red water is colder and is more dense.
The red water is warmer and is less dense.
The red water is warmer and is less dense.
The blue water is colder and is less dense.