(a)[2]
Thermal conduction happens in the metal that makes up the pan. Using particles, describe how thermal conduction takes place in a metal.
(b(i))[1]
State the melting point of ice in kelvin.
(b(ii))[2]
Explain why the water temperature stays unchanged while the ice melts.
(b(iii))[2]
An initial mass of $1.5\,\text{kg}$ of ice starts at $-15^\circ\text{C}$. The specific heat capacity of ice is $2100\,\text{J kg}^{-1}\,^\circ\text{C}^{-1}$. Calculate the energy needed to raise the ice to its melting point.
(b(iv))[2]
Assuming every joule transferred to the pan comes from the heater, use your result from (iii) and Fig. 3.2 to find the heater's power during the warming of the ice.
(b(v))[1]
In Fig. 3.2, the line is less steep for liquid water than for solid water. Suggest one reason for this.