Question 1: Briefly explain what the electromagnetic spectrum is and why different waves within it have different uses.

Answer: The electromagnetic spectrum includes all types of electromagnetic radiation, which differ in wavelength and frequency. These differences determine their uses, such as communication, medical imaging, and sterilisation.

Question 1: Define what is meant by the wavelength and frequency of an electromagnetic wave.

Answer: Wavelength is the distance between successive peaks of a wave, and frequency is the number of wave cycles passing a point per second.

Question 2: Explain why gamma rays are more penetrating than radio waves.

Answer: Gamma rays have much higher energy and shorter wavelengths, allowing them to penetrate materials more effectively than lower-energy radio waves.

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

Answer: Wavelength = c / frequency = (3 × 10^8 m/s) / (6 × 10^19 Hz) = 5 × 10^-12 meters.

Question 2: A radio wave has a wavelength of 3 meters. What is its frequency?

Answer: Frequency = c / wavelength = (3 × 10^8 m/s) / 3 m = 1 × 10^8 Hz.

Question 1: Describe a simple experiment to demonstrate how radio waves can be used for communication. Include the main variables involved and safety precautions.

Answer: An experiment can involve transmitting audio signals via radio waves using a transmitter and receiver. Variables include signal strength, frequency, and distance. Safety precautions include avoiding interference with other electronic devices and ensuring proper grounding of equipment.

Question 1: A medical X-ray machine emits radiation with a wavelength of 0.01 nm. Use the speed of light (3 × 10^8 m/s) to calculate its frequency. Explain why this type of radiation requires safety measures.

Answer: Frequency = c / wavelength = (3 × 10^8 m/s) / (0.01 × 10^-9 m) = 3 × 10^16 Hz. This high frequency and energy can damage living tissues; hence, safety measures like lead shielding and limiting exposure are essential.

Question 1: Explain the differences between radio waves, visible light, and gamma rays in terms of wavelength, energy, and typical uses. Include real-world examples in your answer.

Answer: Radio waves have the longest wavelength and lowest energy, used in communication such as radio broadcasting. Visible light has intermediate wavelength and energy, enabling human sight and applications like photography. Gamma rays have the shortest wavelength and highest energy, used in cancer treatment and sterilisation.

Question 1: Identify one industry that uses microwave radiation and explain how it utilises this wave type, including safety considerations.

Answer: The telecommunications industry uses microwaves for satellite and mobile phone communication. Safety considerations include avoiding prolonged exposure to high-intensity microwaves to prevent tissue heating.

Question 2: Discuss how gamma rays are used in medical treatment and what safety precautions are necessary to protect patients and staff.

Answer: Gamma rays are used in radiotherapy to target and destroy cancer cells. Safety precautions include shielding with lead, limiting exposure time, and remote operation of equipment to protect medical staff and patients from unnecessary radiation.