Scientific Method
A testable prediction, often written in an "If... then..." format.
Hypothesis
Information gathered with your senses or with tools.
Observation
What are the three factors that affect the amount of thermal energy an object has?
Mass, temperature, and state of matter.
The change of state from a liquid to a gas.
Evaporation
The energy of motion.
Kinetic energy
A student tests three fertilizers but gives one plant extra sunlight. Sunlight should have been this type of variable, kept the same for every plant.
Constant
A preliminary conclusion based on observations and prior knowledge.
Inference
Name the three ways heat is transferred and give an example of each.
Conduction, convection, radiation
Why is a liquid considered to have an indefinite shape but a definite volume?
A liquid has a definite volume because its particles are close enough to stay in contact, but it has an indefinite shape because its particles can slide and move freely past one another to take the shape of its container
What is the energy stored in the bonds between atoms? Give two examples.
Chemical energy. Examples: food being consumed, batteries, gasoline, wood burning, photosynthesis
This group does not receive the treatment. Explain why.
Control group. It is used as a baseline comparison in an experiment, which allows scientists to measure what happens naturally without their intervention.
Explain why a scientist must change only one variable at a time during an experiment. What happens to the validity of the experiment if two or more things are changed at once?
Scientists must change only one variable at a time to isolate its specific effect on the outcome, and changing two or more variables at once destroys the experiment's validity because you can no longer tell which change caused the result
A bathtub of 40°C water and a cup of 40°C water have the same temperature, but one of these has more thermal energy. Explain why.
Bathtub, because it has more particles. More particles = more thermal energy.
Condensation releases or absorbs energy? Explain.
It releases energy because particles lose thermal energy as they slow down and move closer together.
Describe the energy transformations in a battery-powered flashlight.
Chemical to electrical to radiant/light. Some energy is lost in the form of heat.
Describe the relationship between the independent and the dependent variable.
There is a cause and effect relationship. The independent variable acts as the cause and the dependent variable acts as the effect. The dependent variable changes in response to changes made to the independent variable.
Why is the idea of a single, rigid, step-by-step "Scientific Method" a myth? How do scientists actually work in the real world?
The idea of a single, rigid, step-by-step "Scientific Method" is a myth because real science is messy, flexible, and repeats and updates over and over.
Describe how convection currents work in a hot air balloon.
A convection current inside the balloon keeps the balloon up as the warm, heated air continually rises, cools and falls to be heated again by the fire that powers the balloon.
Categorize each of these changes of state by whether or not they lose or gain energy to happen: melting, freezing, sublimation, condensation, evaporation
Losing energy: freezing, condensation
Gaining energy: melting, sublimation, evaporation
A roller coaster goes from the top of the first hill to the bottom. Describe how potential and kinetic energy change and explain at which points there's the maximum of each type of energy.
Potential energy is greatest at the top and decreases as the car falls. Kinetic energy increases and is greatest at the bottom.
Name each step of the scientific method and choose one of them to explain in detail.
1. Ask a question
2. Research
3. Make a hypothesis
4. Conduct an experiment
5. Analyze Data
6. Draw a Conclusion
7. Share Results
Explain why scientific knowledge can change over time, and why this is considered a strength of science.
New evidence or technology can show that an earlier explanation was incomplete. Science corrects itself.
Explain the difference between thermal energy, temperature, and heat.
Heat is thermal energy moving from a warmer object to a cooler one
Describe what happens to the motion and arrangement of particles as a solid becomes a liquid and a liquid becomes a gas.
As heat is added, the particles in a solid vibrate faster and move more until they break free from their stuck positions. In a liquid, the particles go from being close together in a fluid state to spreading far apart. They now move fast and randomly in all directions, filling whatever container they are in.
State the law of conservation of energy, and use it to explain why a rolling ball eventually stops.
The law of conservation of energy states that energy cannot be created or destroyed, it can only be transferred or transformed. As a ball rolls, its kinetic energy is transformed into thermal energy and sound due to friction and air resistance. The ball stops once all of its motion energy has completely changed into these other forms!