Specific heat capacity

• What is specific heat capacity?

  It is the amount of energy needed to raise the temperature of 1 kg of a substance by 1°C.
• Why do different materials have different specific heat capacities?

  Because more energy needs to be transferred to some materials to increase their temperature than others.
• How much energy is needed to warm 1 kg of water by 1°C?

  4200 J
• How much energy is needed to warm 1 kg of mercury by 1°C?

  100 J
• What happens to materials that have high specific heat capacities when they cool down?

  They transfer loads of energy when they cool down and can store a lot of energy.
• What is the equation that links energy transferred to specific heat capacity?

  ∆E = mc∆θ
• What are the steps to investigate specific heat capacities of solid materials?

  1. Measure the mass of the block.
  2. Wrap it in an insulating layer.
  3. Insert thermometer and heater.
  4. Measure initial temperature and set power supply to 10 V.
  5. Turn on power and start stopwatch.
  6. Record temperature and current every minute for 10 minutes.
  7. Calculate power supplied using P = VI.
  8. Calculate energy transferred using E = Pt.
  9. Plot graph of energy transferred against temperature.

  10. Find gradient to determine specific heat capacity.
• How do you calculate the power supplied to the heater in the experiment?

  Using the formula P = VI.
• How can you calculate the energy transferred to the heater at each temperature reading?

  Using the formula E = Pt, where t is the time in seconds.
• What does the gradient of the straight part of the graph represent in the specific heat capacity experiment?

  It represents ∆E/∆θ.
• How do you find the specific heat capacity of the material of the block from the graph?

  By calculating (1 ÷ gradient) x the mass of the block.
• What is the specific heat capacity of water?

  4200 J/kg°C
• What is the significance of specific heat capacity in practical applications?

  • Determines how materials respond to heat.
  • Influences energy efficiency in heating and cooling systems.
  • Affects temperature control in various processes.