Thermal energy IV - JSS2 Basic science Past Questions and Answers - page 1

Radiation transfers heat through electromagnetic waves, unlike convection which requires the movement of fluid (like air or water), and conduction which occurs through direct contact between materials.

One example is the use of infrared radiation in remote controls to operate electronic devices. When you press a button on a remote control, it emits infrared radiation that communicates with the device, allowing you to change channels or adjust settings without needing direct line-of-sight.

Radiation plays a crucial role in maintaining the Earth's temperature balance. For instance, the Sun emits radiation, which warms the Earth's surface. Some of this radiation is then absorbed by the Earth and re-emitted as infrared radiation. Greenhouse gases in the atmosphere trap some of this infrared radiation, preventing it from escaping into space and helping to keep the Earth warm enough to support life. However, human activities, such as burning fossil fuels, can increase the concentration of greenhouse gases, leading to an enhanced greenhouse effect and global warming.