physics 9b (particle model.)

• the internal energy of a system is the total kinetic energy and potential energy of all the particles in a system.
• the potential energy is due to separation (distance.) between particles. It increases as separation increases.
• the kinetic energy is due to movement. The faster the particles are moving then the greater their kinetic energy.
• Density (kg/m3) = mass (kg)/volume (m3)​
• Latent Heat= Changes the state of the substance but not it's temperature.​
• Specific Heat= Changes the temperature of a substance but not it's state.​
• Gas pressure in a container is caused by the force imparted by the gas particles colliding with the walls of that container.​
• Reducing the volume of the container means the gas particles have less distance to travel before they hit the container walls. They are therefore hitting more often so the pressure goes up.​
• Increasing the temperature means the gas particles move faster and hit more often with more force so the pressure goes up.​
• work done= force (N) x distance (m)
• doing work on a gas

  • When a gas is compressed a force is used to compress it (move it.)
  • Energy is transferred in compressing a gas, so work is done on the the gas.
  • Doing work on the gas increases the internal energy of the gas.
• Diffusion- particles spread out from area of high concentration to an area of low concentration.