1.1.3 Describing Energy Changes in a System

• A system in physics is an object or group of objects considered together as a unit for analysis
• What are boundaries in a system?

  Limits defining the system
• Kinetic energy is associated with motion.


  True
• Elastic potential energy is stored in a stretched or compressed object.
• What is thermal energy caused by?

  Temperature
• Kinetic energy is associated with motion
• Open systems can exchange matter with their surroundings.

  True
• What type of system cannot exchange matter with its surroundings?

  Closed system
• What type of energy transfer involves a force moving an object?

  Work
• Heat transfer occurs due to a temperature difference.


  True
• What is a system in physics defined as?

  A group of objects
• Objects within a system are physical items.


  True
• Interactions within a system involve forces and transfers
• What is gravitational potential energy due to?

  Height
• Chemical energy is stored in chemical bonds.

  True
• Match the energy store with its definition:

  Gravitational Potential Energy ↔️ Energy due to height

  Chemical Energy ↔️ Energy stored in chemical bonds

  Thermal Energy ↔️ Energy due to temperature
• Energy changes in a system occur due to energy transfers
• What type of energy is associated with motion?

  Kinetic energy
• Gravitational potential energy is due to an object's height
• Where is chemical energy stored?

  Chemical bonds
• What type of system is a cup of hot coffee that can exchange both energy and matter with its surroundings?

  Open system
• Open systems can exchange both energy and matter with their surroundings.

  True
• A cup of hot coffee is an example of an open system because it exchanges both energy and matter.
• Match the energy transfer type with its description:

  Work ↔️ Force moving an object

  Heat ↔️ Temperature difference

  Electrical Energy ↔️ Electric charge

  Radiation ↔️ Energy emitted as waves
• Energy transformations involve converting energy from one form to another.


  True
• Energy transfers include work, heat, electrical energy, and radiation.
• What energy transformations occur in a power plant?

  Chemical to heat to electrical
• Match the system with its energy transformations:

  Power Plant ↔️ Heat to electrical energy

  Car Engine ↔️ Chemical to kinetic energy

  Human Body ↔️ Chemical to mechanical energy

  Solar Panel ↔️ Light to electrical energy
• Match the energy transfer with its description:

  Heat ↔️ Energy transferred due to temperature difference

  Electrical Energy ↔️ Energy carried by electric charge

  Radiation ↔️ Energy emitted as waves
• Elastic potential energy is stored in a stretched or compressed object.

  True
• Open systems cannot exchange matter with their surroundings.

  False
• A sealed thermos containing hot coffee is a closed system because it can only exchange energy, not matter, with its surroundings.
• What can a closed system exchange with its surroundings?

  Energy only
• What are the four types of energy transfers mentioned in the material?

  Work, heat, electrical energy, radiation
• Pushing a box across the floor is an example of energy transfer through work.
• What is an example of energy transfer through radiation?

  Sun heating Earth
• What is an example of energy transformation from chemical energy to kinetic energy?

  Food being used for movement
• Match the energy transfer type with its example:

  Work ↔️ Pushing a box

  Heat ↔️ Warming hands by a fire

  Electrical Energy ↔️ Lighting a bulb

  Radiation ↔️ Sun heating Earth
• The human body transforms chemical energy from food into mechanical and heat energy.


  True
• Order the following energy transfer types from least to most common examples:

  1️⃣ Electrical Energy

  2️⃣ Radiation

  3️⃣ Heat

  4️⃣ Work