Energy is the mover and shaker of the universe. Heat from the sun, sounds from your radio, riding a bike and watching a movie are all expressions of different forms of energy.
As you sit there reading this, there is energy flowing all around you in the form of light waves, sound waves, radio waves, heat and more. You are constantly being bombarded by energy.
Energy is everywhere, all the time. We’re going to focus on simple machines (pulleys, levers, and pendulums) that make use of mechanical advantage as well as studying several methods of finding, converting, storing and using renewable and alternative energy.
Here are the scientific concepts:
- Energy can be carried from one place to another by heat flow, or by waves including water waves, light and sound, or by moving objects.
- When fuel is consumed, most of the energy released becomes heat energy.
- Heat flows in solids by conduction (which involves no flow of matter) and in fluids by conduction and also by convection (which involves flow of matter).
- Heat energy is also transferred between objects by radiation; radiation can travel through space.
- The sun is the major source of energy for phenomena on the Earth’s surface, powering winds, ocean currents, and the water cycle.
- Solar energy reaches Earth through radiation, mostly in the form of visible light.
- Heat from Earth’s interior reaches the surface primarily through convection.
- Convection currents distribute heat in the atmosphere and oceans.
- Differences in pressure, heat, air movement, and humidity result in changes of weather.
- The utility of energy sources is determined by factors that are involved in converting these sources to useful forms and the consequences of the conversion process.
- Different natural energy and material resources, including air, soil, rocks, minerals, petroleum, fresh water, wildlife, and forests, and classify them as renewable or nonrenewable.
- Natural origin of the materials used to make common objects.
- Motion energy is properly called kinetic energy; it is proportional to the mass of the moving object and grows with the square of its speed.
- A system of objects may also contain stored (potential) energy, depending on their relative positions.
- Temperature is a measure of the average kinetic energy of particles of matter. The relationship between the temperature and the total energy of a system depends on the types, states, and amounts of matter present.
- When the motion energy of an object changes, there is inevitably some other change in energy at the same time.
- The amount of energy transfer needed to change the temperature of a matter sample by a given amount depends on the nature of the matter, the size of the sample, and the environment.
- Energy is spontaneously transferred out of hotter regions or objects and into colder ones.
- When two objects interact, each one exerts a force on the other that can cause energy to be transferred to or from the object.
By the end of the labs in this unit, students will be able to:
- Know how to demonstrate how solar energy reaches Earth through radiation, mostly in the form of visible light.
- Understand how to determine that energy can be carried from one place to another by waves, such as water waves and sound, by electric current, and by moving objects.
- Differentiate observation from inference (interpretation) and know scientists’ explanations come partly from what they observe and partly from how they interpret their observations.
- Measure and estimate the weight, length and volume of objects.
- Formulate and justify predictions based on cause-and-effect relationships.
- Conduct multiple trials to test a prediction and draw conclusions about the relationships between predictions and results.
- Construct and interpret graphs from measurements.
- Follow a set of written instructions for a scientific investigation.