Dangers of Electromagnetic Waves | Physics for GCSE/IGCSE - Year 11 PDF Download

Dangers of Electromagnetic Waves

• As the frequency of electromagnetic (EM) waves rises, their energy also increases.
• Once beyond the visible spectrum, the energy of EM waves becomes sufficient to ionize atoms.
• Consequently, the risk associated with EM waves escalates alongside their frequency.
  • Shorter wavelengths indicate more ionizing radiation.
  • However, the intensity of a wave also holds significant importance.

• Due to ionization, ultraviolet waves, X-rays, and gamma rays can pose risks to human body tissue.
  • The impact varies based on the radiation type and the dosage.
• These waves have the potential to harm cells and induce mutations, leading to cancer.
• Broadly, electromagnetic waves become increasingly hazardous as their wavelengths shorten.
  • For instance, radio waves lack known harmful effects, whereas gamma rays, highly perilous, can induce cancer.
• The primary dangers associated with electromagnetic waves are outlined in the following table:
  
• The uses and hazards of various EM waves are outlined in the diagram provided below:
  

Microwaves

• Certain frequencies of microwaves are absorbed by water molecules
• Since humans have a high water content, there is a risk of internal heating from microwaves
• Microwaves used in everyday circumstances, like those in mobile phones, emit small amounts of energy and are considered safe
• Microwave ovens emit large amounts of energy, but the metal walls and grid in the glass door prevent the energy from escaping
  • Microwaves used for communication, such as in mobile phones, emit low levels of energy that are considered safe.
  • Microwave ovens emit high amounts of energy, but the metal walls and grid in the glass door contain this energy.
• Microwaves in communication devices emit safe levels of energy.
• Microwave ovens trap high energy levels within their metal construction.

Ultraviolet (UV) Radiation

• UV radiation, invisible to the human eye, carries high energy levels.
• Excessive UV exposure can lead to severe eye damage, but quality sunglasses can block UV rays.
  • High levels of UV exposure can cause significant harm to the eyes.
• UV radiation can be ionizing, potentially harming cells and leading to conditions like premature aging and skin cancer.
  • Sunscreen helps prevent UV damage to the skin.

X-rays and Gamma Rays

• X-rays and gamma rays are highly ionizing forms of electromagnetic waves.
• They can penetrate the body, leading to internal damage and potential gene mutations that may cause cancer.
• These rays have the capability to cause internal harm and genetic mutations, which can result in cancer.
• In medicine, X-ray levels are kept minimal to reduce risks. Doctors limit exposure by leaving the room during scans.
• Professionals handling gamma rays take precautions to minimize exposure and undergo regular radiation dose monitoring.
• Medical staff like radiographers wear radiation badges to measure their exposure levels.
• When taking X-rays, doctors will exit the room to prevent unnecessary exposure.
• Individuals handling gamma rays must take various precautions to minimize their exposure and undergo regular radiation dose assessments.
• For instance, medical professionals like radiographers wear radiation badges to gauge their radiation exposure levels.