An object falls freely near Earth's surface. Which graph best represents the relationship between the object's kinetic energy and time elapsed during its fall?
A.
B.
C.
D.
The correct graph that best represents the relationship between the object's kinetic energy and time elapsed during its fall would be graph D.
The picture below shows Peggy's new racetrack. It has different starting positions and an upside-down loop for cars to go through. She has 3 cars that she wants to try on the track: a sports car, a truck, and a jeep.
Peggy knows that height can change how fast a car will go. Which experiment will help Peggy choose the starting position that allows every car to complete the loop?
A.
an experiment where Peggy drops each car from different starting heights multiple times and records which heights allow all three cars to complete the loop every time
B.
an experiment where Peggy drops each car from the same starting height and measures the amount of time it takes each car to complete the loop
C.
an experiment where Peggy drops each car from different starting heights multiple times and measures how far each car goes on the course after completing the loop
D.
an experiment where Peggy drops each car from the same starting height and records which cars complete the loop from that height
The correct answer is A. an experiment where Peggy drops each car from different starting heights multiple times and records which heights allow all three cars to complete the loop every time. This experiment will help Peggy determine the starting position that allows every car to complete the loop consistently, regardless of their individual characteristics like size or weight.
Students are investigating energy transfer in the laboratory. The students use rubber bands and rulers for their investigation. They attach a rubber band to each ruler, pull the band back, and allow the band to launch from the ruler. The diagram shows their set up.
The results of their investigation are shown.
Ruler Distance Band Is Pulled Back
(centimeters) Distance Band Travels (centimeters)
1 5 61
2 10 122
3 15 213
4 20 366
Which statement best describes the results of their investigation?
A.
The more potential energy the band has, the more kinetic energy is transferred, and the farther the band travels.
B.
The less potential energy the band has, the more kinetic energy is transferred, and the farther the band travels.
C.
The more kinetic energy the band has, the more potential energy is transferred, and the farther the band travels.
D.
The less kinetic energy the band has, the more potential energy is transferred, and the farther the band travels.
The best statement that describes the results of their investigation is A. The more potential energy the band has, the more kinetic energy is transferred, and the farther the band travels. This is evident from the data where as the distance the band is pulled back (potential energy) increases, the distance the band travels (kinetic energy) also increases.
A student is investigating the transfer of potential energy into kinetic energy. The student uses a slingshot and a marble, as shown in the diagram.
The steps of the student's investigation are shown.
Step 1 Place the marble in the slingshot, pull back on the sling to a distance of 15 centimeters, release the sling, and record the distance the marble travels.
Step 2 Place the marble in the slingshot, pull back on the sling to a distance of 10 centimeters, release the sling, and record the distance the marble travels.
Step 3 Place the marble in the slingshot, pull back on the sling to a distance of 5 centimeters, release the sling, and record the distance the marble travels.
What will MOST LIKELY be the result of this investigation?
A.
The marble released from a distance of 5 centimeters will have the most potential energy transferred into kinetic energy, causing the marble to travel the farthest.
B.
The marble released from a distance of 15 centimeters will have the most potential energy transferred into kinetic energy, causing the marble to travel the farthest.
C.
The marble released from a distance of 5 centimeters will have the least potential energy transferred into kinetic energy, causing the marble to travel the farthest.
D.
The marble released from a distance of 15 centimeters will have the least potential energy transferred into kinetic energy, causing the marble to travel the farthest.
The most likely result of this investigation is B. The marble released from a distance of 15 centimeters will have the most potential energy transferred into kinetic energy, causing the marble to travel the farthest. This is because the potential energy in the rubber bands is directly proportional to the distance the bands are pulled back. Therefore, the farther the slingshot is pulled back, the more potential energy is stored, which is then transferred into kinetic energy when the sling is released.
The diagram models a device that was the foundation for the modern electrical turbine.
Which of the following is causing the wheel to turn?
A.
Force from the mechanical energy generated by the solar radiation causes the wheel to turn.
B.
Force from the mechanical energy generated by the moving water causes the wheel to turn.
C.
Force from the thermal energy generated by the solar radiation causes the wheel to turn.
D.
Force from the thermal energy generated by the moving water causes the wheel to turn.
The correct answer is B. Force from the mechanical energy generated by the moving water causes the wheel to turn. In the diagram, it is shown that the wheel is connected to a water source, indicating that the movement of water is responsible for causing the wheel to turn. This mechanical energy is then harnessed to generate electricity in a turbine.
The table describes the qualities of four objects.
Object Produces Light? Temperature (°C/°F)
a bouncing basketball no 20°C/68°F
the Sun's surface yes 5500°C/10,000°F
a lit lightbulb yes 250°C/482°F
a fork sitting on a table no 15°C/59°F
Which of the following is most likely true?
A.
Small objects produce more light than larger objects.
B.
Large objects produce less heat than smaller objects.
C.
Objects that produce light energy often produce heat energy.
D.
Objects that do not produce light energy have high temperatures.
The most likely true statement based on the given information is C. Objects that produce light energy often produce heat energy. This is supported by the fact that the objects that produce light in the table, such as the Sun's surface and a lit lightbulb, also have higher temperatures listed. Light energy is often a byproduct of heat energy, as in the case of the Sun or a lit lightbulb.
The diagram below shows two flasks of water, one with hot water and the other with room temperature water, which are connected by a conductive metal bar.
When initially set up, in which direction does the thermal energy between the flasks flow?
A.
Thermal energy flows from the flask on the left to the flask on the right.
B.
Thermal energy flows from the flask on the right to the flask on the left.
C.
Thermal energy does not flow between the two flasks.
D.
Thermal energy flows equally between the two flasks.
The correct answer is A. Thermal energy flows from the flask on the left to the flask on the right. This is because heat energy generally flows from an object with a higher temperature to an object with a lower temperature until both objects reach thermal equilibrium. Therefore, the hot water in the flask on the left will transfer its thermal energy to the cooler room temperature water in the flask on the right.
A piece of metal is heated and then submerged in cool water. Which statement below best describes what happens?
A.
The temperature of the water will decrease, while the temperature of the metal will increase.
B.
The temperature of the water will decrease and the temperature of the metal will also decrease.
C.
The temperature of the water will increase, while the temperature of the metal will decrease.
D.
The temperature of the water will increase and the temperature of the metal will also increase.
The correct answer is C. The temperature of the water will increase, while the temperature of the metal will decrease. When a piece of metal is heated and then submerged in cool water, heat energy will transfer from the metal to the water. This transfer of heat will cause the temperature of the water to increase as it gains thermal energy from the metal. At the same time, the metal will lose thermal energy to the water, causing its temperature to decrease.
In an engine, fuel and oxygen chemically react and release energy. What happens to the energy NOT used by the engine?
A.
It has been destroyed.
B.
It is lost in the form of heat and sound.
C.
It remains stored in the chemical bonds of the fuel.
D.
It is converted into methane.