WAEC Physics 2015 Theory — Question 12

Model answer

(a) Specific latent heat of vaporization is the quantity of heat energy required to change a unit mass of a liquid from its liquid state to its gaseous state without a change in temperature. Its S.I. unit is Jkg⁻¹. (b) Renewable energy sources are naturally and continually replenished energy sources that place themselves back after they have been used, and so cannot be exhausted - examples include solar, wind, biomass, hydroelectric, geothermal and tidal energy.