Inv. 4 “Heat Transfer” FOSS Weather and Water Grade 6

Heating Water Water takes 5 times more heat energy to raise an amount of water one degree than it takes to raise the temperature of an equal amount of dry soil or sand one degree. SUN SUN 1°C 5°C Water Soil

Heating Water If a kilogram of water and a kilogram of soil absorb equal amounts of solar energy, the temperature of the soil will be much higher than the temperature of the water. The water doesn’t get as hot, but it absorbed the same amount of heat energy.

Radiant Energy Energy that comes from the Sun as radiant energy. Radiant energy travels as waves through space and through air.

Radiation Radiation from the Sun can be: Visible: light Invisible: infrared radiation, U.V. radiation, microwave, X-ray, etc….

Energy Transfer When radiant energy strikes an atom or molecule, like a water molecule, or a molecule in sand, soil, or air, the molecule gains energy and begins to move faster. The molecule absorbed radiant energy. Absorbing radiant energy is one way energy transfers to matter.

Motion of Molecules Molecular motion is heat. The more motion there is in the molecules of matter, the hotter the particles get.

Radiant Energy Radiation is one way energy can travel over great distances or short distances. Radiant energy travels through the vacuum of space, some wavelengths travel through air and other transparent materials (glass, plastic, water…) Radiant energy is energy transfer at a distance without direct contact between the energy source and the energy receiver.

Differential Heating Different materials heat up at different rates = differential heating. Differential heating accounts for the difference in temperature of water and soil after they have both been in the sunshine for the same length of time.

Differential Heating Water in oceans and lakes can store more heat than landmasses, even though the temperature of the water may be lower. Multimedia: FOSS Weather and Water “Heat Energy”