Potential and Kinetic Energy
What kind of energy does a ball sitting at the top of a hill have?
Gravitational Potential Energy
Give one example of chemical energy students encounter in food.
Food, gasoline, or burning something
What is thermal energy?
Thermal energy is the total energy of moving particles in a substance (heat)
Give two examples of abiotic (nonliving) factors in an ecosystem.
Examples: sunlight, water, soil, temperature, rocks.
What is a producer? Give one example.
Producer: organism that makes its own food via photosynthesis (example: algae).
When a skateboarder rolls down a ramp, which energy increases?
Kinetic Energy
What type of energy is carried by light from the Sun that plants use for photosynthesis?
Radiant energy, light energy, or electromagnetic radiation.
Name the three methods of thermal energy transfer.
Conduction, convection, radiation
Give two examples of biotic (living) factors in an ecosystem.
Examples: plants, animals, bacteria, fungi.
In a simple food chain, who eats producers and what is that role called?
Primary consumers or herbivores eat producers
Identify whether each situation is primarily kinetic or potential energy: (a) flowing river, (b) stretched rubber band, (c) parked car on a hill.
(a) kinetic, (b) elastic potential, (c) gravitational potential.
Define thermal energy and give an everyday example.
The total kinetic and potential energy of the particles in an object.
Fire, body heat, or ice cube.
Describe an example that shows thermal energy transfer by conduction.
Example: a metal spoon becoming hot from the soup by direct contact (conduction)
How could a drought (less water) affect a population of frogs in a pond?
Drought reduces pond water.
Fewer breeding sites, less food, higher concentration of pollutants → frog population likely declines.
Draw (describe) a short food chain with 4 levels and label each level (producer, primary consumer, secondary consumer, and tertiary consumer).
Algae (producer) → zooplankton (primary consumer) → small fish (secondary consumer) → heron (tertiary consumer)
A 2-kg object is lifted 3 meters above the ground. Name which form of potential energy this is and describe one factor that would change its amount.
Gravitational Potential Energy
The factors that would change the amount of energy are either mass or height.
Describe chemical potential energy and explain how it changes during digestion in animals.
Chemical potential energy in food is broken down into kinetic energy and thermal energy during digestion/eating.
Explain how convection moves thermal energy in the atmosphere or in boiling water.
Warm air rises and cool air sinks, creating convection currents; in boiling water, hotter water rises and cooler water sinks.
Using data (e.g., fewer plants, lower oxygen, higher temperature), explain one way an abiotic change could reduce a population size of a species.
Example answer: A drought would lower the amount of water in an area and cause there to be less herbivores due to low plant growth.
Explain why energy pyramids usually get narrower at the top. Relate your answer to transfers of energy between trophic levels.
Energy is lost (mostly as thermal energy) at each transfer; only a fraction (~10%) moves to the next level, so less energy supports fewer organisms at higher levels.
Explain how energy is conserved when a pendulum swings from its highest point to its lowest point. Include references to kinetic and gravitational potential energy.
At highest point, energy mostly gravitational potential; at lowest point, mostly kinetic. Total mechanical energy (ignoring friction) stays the same; with friction some energy becomes thermal.
Compare and contrast elastic potential energy and gravitational potential energy with an example for each.
Elastic: energy stored in stretched/compressed objects (stretched rubber band). Gravitational: energy due to position in a gravitational field (book on shelf).
Use the idea of energy conservation to explain what happens to the thermal energy and other forms of energy when a toy car hits a wall and stops.
Kinetic energy of the car’s motion is transferred into deformation of materials and heat (thermal energy) and sound; overall energy is conserved but changes forms.
A new predator is introduced. Describe how adding a new predator could affect multiple populations in an ecosystem.
Adding a new predator could lower herbivore populations and that would cause a rising in producers.
Describe how energy flows through a food web in a pond ecosystem and explain how removing one species (like a top predator) could change energy flow and population sizes.
Removing top predator may increase large fish, which decreases small fish, increasing zooplankton pressure on algae, possibly reducing algae and changing primary production and energy available to the whole web.