Work on a gas

• What does the pressure of a gas cause in a container?

  A force that pushes outwards against the container
• How do gas particles behave in a container?

  They move randomly at high speed, spreading out in the container
• What happens when gas particles collide with the walls of the container?

  They create an outward force or pressure
• What must be done to compress a gas in a container?

  Work must be done against the outward force of the gas
• What is work defined as in the context of forces?

  When forces cause a change in energy
• How does compressing gas affect its particles?

  It causes the particles to gain speed as they bounce off the walls
• What happens to the kinetic energy of gas particles when they are compressed?

  The kinetic energy increases
• How is the temperature of a gas related to its kinetic energy?

  The temperature is a measure of the kinetic energy of its molecules
• What is a common scenario where we notice a change in temperature when compressing gas?

  Pumping up a bicycle tire with a pump
• What happens to the pump when we quickly pump up a bicycle tire?

  The end of the pump becomes hot
• Why does the temperature of the air in the pump increase when pumping quickly?

  Because work is done against the pressure of the air
• What occurs if we pump up the tire slowly?

  We probably wouldn't notice a change in temperature
• What is the relationship between work done and internal energy during gas compression?

  • Work done transfers energy to the internal energy of the gas
  • Increased internal energy leads to increased kinetic energy of particles
  • Higher kinetic energy results in higher temperature of the gas
• What are the effects of compressing gas on its temperature and internal energy?

  • Compression increases the kinetic energy of gas particles
  • Increased kinetic energy raises the internal energy of the gas
  • Higher internal energy correlates with higher temperature
• What happens to the temperature of air in a bicycle pump when pumping quickly?

  • The temperature increases due to work done against air pressure
  • The end of the pump becomes hot to touch
  • Faster pumping leads to more noticeable temperature change
• What is the difference in temperature change when pumping a tire quickly versus slowly?

  • Quickly: noticeable increase in temperature
  • Slowly: minimal temperature change as the pump cools down