Question 1: Define electromagnetic waves and explain how they propagate through space.

Answer: Electromagnetic waves are oscillations of electric and magnetic fields that propagate through space at the speed of light without needing a medium.

Question 2: List the main types of electromagnetic waves in order of increasing wavelength.

Answer: Gamma rays, X-rays, Ultraviolet, Visible light, Infrared, Microwaves, Radio waves.

Question 3: Describe how radio waves are used in environmental monitoring systems.

Answer: Radio waves are used in sensors and communication devices to detect pollution levels, monitor weather patterns, and track wildlife migration without disturbing the environment.

Question 1: Calculate the wavelength of a gamma ray with a frequency of 6 x 10^19 Hz. (Use the speed of light c = 3 x 10^8 m/s)

Answer: Wavelength λ = c / f = (3 x 10^8 m/s) / (6 x 10^19 Hz) = 5 x 10^-12 meters

Question 2: A microwave used in environmental sensors operates at a frequency of 2.45 GHz. What is its wavelength?

Answer: λ = c / f = (3 x 10^8 m/s) / (2.45 x 10^9 Hz) ≈ 0.122 meters

Question 1: Design a basic experiment to detect infrared radiation from environmental sources. Mention the key variables and safety precautions.

Answer: Use an infrared sensor or camera to detect IR radiation emitted by sources like heated rocks or plants. Variables include source temperature and distance. Safety precautions involve avoiding direct exposure to intense IR sources to prevent burns and ensuring proper handling of electronic equipment.

Question 2: Explain why UV rays can be harmful to the environment and what safety measures should be taken when studying UV radiation.

Answer: UV rays can cause skin damage, harm wildlife, and degrade materials. Safety measures include wearing UV-protective clothing, using sunglasses, and limiting exposure time.

Question 1: A satellite detects increased levels of infrared radiation over a forest area, indicating possible deforestation or forest fire. Explain how infrared sensors help in environmental monitoring and what limitations they might have.

Answer: Infrared sensors detect heat emitted by objects, allowing monitoring of temperature changes and identifying areas of deforestation or fires. Limitations include interference from weather conditions like clouds or fog and the need for calibration to distinguish between natural and abnormal heat sources.

Question 1: Explain how the different regions of the electromagnetic spectrum are utilised in environmental science, including examples of applications for each type.

Answer: Radio waves are used in communication and remote sensing for weather forecasting. Microwaves assist in radar systems and environmental monitoring. Infrared radiation helps detect heat emissions from natural sources and pollution. Ultraviolet light is used in sterilisation and studying ozone depletion. X-rays are mainly used in imaging, but can also help in detecting pollution in geological studies. Gamma rays are employed in advanced environmental research and sterilisation processes. Each region's unique properties enable specific applications relevant to environmental protection and monitoring.

Question 1: Discuss how satellite technology uses different parts of the EM spectrum to monitor climate change and environmental health.

Answer: Satellites use radio waves for communication, infrared sensors to measure surface temperatures, ultraviolet imaging to monitor ozone levels, and visible light to observe land use changes. These tools provide comprehensive data aiding climate change predictions and environmental management.