Heating and Insulating Buildings

U values measure how effective a material is as an insulator

It is defined as the rate of heat flow in

watts (W) through

an area of 1 square metre (m) for a

temperature difference across the

structure

of 1 C degree centigrade You don’t need this

definition!

The lower the U-value, the better the material is as an insulator

Specific Heat Capacity

The specific heat capacity of a substance is the amount of energy

required to change the temperature of one kilogram of the

substance by one degree Celsius

Practical set up

Experiment to find out the SHC of a substance

• The metal I’m testing is ___________. • Mass of metal _____________• Initial temperature =• Final temperature after 8 minutes =• Change in temperature = • Time in seconds = • Current = • Voltage =• Power = current × voltage • Energy transferred to the metal in 8 minutes = power

× time (seconds) Challenge: What is the SHC of the metal?

Equation to calculate specific heat capacity

The SHC of Water is 4200 J/Kg/oC