Infrared radiation absorption and radiation by a surface

• The amount of infrared radiation absorbed or radiated by a surface depends on the nature of that surface.
• The Earth’s temperature also depends on the rates at which light and infrared radiation are absorbed by the Earth’s surface and atmosphere.
• The method described here uses a Leslie cube, a metal cube with four different types of surface, filled with hot water to increase its temperature.
• The aim of the experiment is to investigate how the amount of infrared radiation absorbed or radiated by a surface depends on the nature of that surface.
• The experiment involves placing a Leslie cube on a heat-resistant mat, filling it, almost to the top, with boiling water and replacing the lid, leaving for one minute to enable the surfaces to heat up to the temperature of the water.
• The infrared detector is used to measure the intensity of infrared radiation emitted from each surface, or the temperature of the surface.
• The detector must be placed the same distance from each surface before taking a reading.
• Hazards and control measures include boiling water, which can cause scalds, so pour water slowly, using a funnel if necessary, and do not move the Leslie cube until it has cooled.