CP12 & CP13

• What is temperature?


  A measure of how hot a substance is, indicating the movement of particles.
• What is thermal energy?


  The energy stored in hot objects, which increases with temperature.
• What is specific heat capacity?


  The energy needed to raise 1 kg of a substance by 1 degree Celsius.
• What is specific latent heat?


  The energy needed to change the state of 1 kg of a substance without a change in temperature.
• What is the equation for energy using specific heat capacity?


  Energy = Mass × specific heat capacity × change in temperature.
• What is the equation for energy using specific latent heat?


  Energy = mass × specific latent heat.
• What is specific latent heat of fusion?


  The energy required to melt 1 kg of a substance without a change in temperature.
• What is latent heat of vaporisation?


  The energy required to boil 1 kg of a substance without a change in temperature.
• What is the formula for density?

  Density = mass / volume.
• What is density?


  The mass of a certain volume of the substance.
• What is the kinetic theory?


  It states that everything is made out of tiny particles.
• What does the amount of thermal energy stored in something depend on?


  It depends on temperature, mass, and the material it's made from.
• What causes gas pressure?


  The forces on the wall of a container caused by moving particles hitting the wall.
• What is the unit for pressure?


  Pascals (Pa).
• If you increase the temperature of a gas, what happens to the pressure?


  The pressure increases.
• Why does increasing the temperature of a gas increase its pressure?


  Because the particles speed up, leading to more frequent collisions and greater force exerted.
• What is absolute zero?


  0 Kelvin or -273°C.
• Why is it called absolute zero?


  Because if a gas could be made this cold, its pressure would be zero.
• What is the Kelvin temperature scale?


  It measures temperature relative to absolute zero.
• How do you convert from Kelvin to degrees Celsius?


  Subtract 273.
• How do you convert from degrees Celsius to Kelvin?


  Add 273.
• What is extension?


  The length that it changes when a force is applied.
• What is elastic limit?


  The point at which an object will stop behaving as an elastic object.
• What causes an object to change shape?

  Forces can deform or change the shape of an object, and materials can be elastic or inelastic.
• What do we see when plotting the length of a spring against the force applied?


  A linear relationship, where force increases as the length of the spring increases.
• What is the formula for force in relation to spring constant and extension?


  Force = spring constant × extension.
• What is the formula for energy transferred in stretching a spring?


  Energy transferred in stretching = 0.5 × spring constant × extension².
• Explain how stretching, bending, or compressing an object requires more than one force.


  Stretching, bending, or compressing an object requires more than one force acting on it.
• Describe the difference between elastic and inelastic distortion.


  Elastic distortion allows the object to return to its original shape, while inelastic distortion keeps the new shape.
• Recall the equation for linear elastic distortion.


  Force exerted on a spring = spring constant × extension.
• Recall the equation for work done in stretching a spring.


  Energy transferred in stretching = 0.5 × spring constant × extension².
• Describe the difference between linear and non-linear relationships between force and extension.


  A linear relationship occurs with a metal spring, while a non-linear relationship occurs with rubber bands or overstretched springs.
• What is the core practical for investigating the extension and work done when applying forces to a spring?


  • Investigate the extension of a spring under various forces.
  • Measure the work done in stretching the spring.
• Explain why atmospheric pressure varies with height above the Earth's surface.


  Atmospheric pressure decreases with height due to the weight of the air above.
• Describe the pressure in a fluid.


  Pressure in a fluid is due to the depth of the fluid and atmospheric pressure.
• Recall that the pressure in fluids causes a force normal to any surface.


  The pressure in fluids exerts a force perpendicular to any surface it contacts.
• Explain how pressure is related to force and area.


  Pressure is the measure of force on a unit area, where the force is normal to the surface.
• Recall the equation for pressure.

  Pressure = force normal to surface / area of surface.
• Describe how pressure in fluids increases with depth and density.


  Pressure increases with depth due to the weight of the fluid above and depends on the fluid's density.
• Explain why pressure in liquids varies with density and depth.


  Pressure in liquids increases with depth due to the weight of the liquid above and is greater in denser liquids.