Science

Unit 1- Thermal Energy (How does a change in thermal energy affect matter?)

All things are made of molecules that are tiny particles we can’t see. These molecules can change in motion and temperature when heated or cooled. The heat is called thermal energy and it can be measured and transferred. Our weather results from thermal energy.

Unit 2- Chemical Reactions (What are chemical reactions?)

All matter is composed of solid, liquids and gases. Density is a property of all matter and depends on how close the molecules are. Molecules vibrate and collide because of the energy they contain. Molecules in solids are packed closely together so they have less movement and less collisions. Liquids take the shape of the container they occupy so molecule interaction will depend on the liquid and container. Gasses have free movement unless they are compressed (under pressure) and molecule interactions increase. Chemical reactions occur when two substances are combined. When this happens a new product is formed, but the total number of atoms is the same. In some chemical reactions thermal energy(heat) is transferred. Chemical reactions are used to create products that we use everyday. (Plastic is an example of a chemical reaction.)

Unit 3- Ways Energy is Transferred (What happens when energy is transferred?)

All moving objects have energy. When an object is in motion it has kinetic energy that can be transferred if two or more objects collide. Kinetic energy is related to the size (mass) and speed of an object. Newton’s Third Law describes how kinetic energy is transferred when objects collide. Light particles (photons) and sound waves also contain energy. The energy of sound and light is described by wavelength, amplitude and frequency. The energy from sound and light can pass through some materials, but not through others. The range of energy transmission for sound and light is also limited. This makes light and sound less reliable for transmitting information through certain materials and for great distances. Digitized signals used in computer information processing use a binary sequence (on/off bits of information) that don’t weaken over distances so they are more reliable.

Unit 4- How Objects Interact (How can objects interact at a distance?)

Energy can exist as electrical current and magnetism. Electrical and magnetic forces can have different strengths. The strength between objects in a magnetic or electrical field depends on the distance between them. Our solar system is held by gravitational forces that also depends on the size of planets and stars interacting. Any change in the distance between objects will affect the potential energy stored in the system.

Unit 5- Natural Resources (How important are our natural resources?)

Energy acts to stabilize our solar system as well as our ecosystems on Earth. Organisms in our ecosystems interact to maintain balance. Multiple ecosystems can interact together. Our bodies also use energy to maintain a balance. When all body systems interact in balance, we are healthy. Any disturbance in the energy of a system will create disequilibrium whether the system is in space, the environment or our bodies.