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Electromagnetic Waves — Physics STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 SciencePhysicsElectromagnetic Waves3 Marks
Question
  1. Which segment of electromagnetic waves has highest frequency? How are these waves produced ? Give one use of these waves.
  2. Which em waves lie near the high-frequency end of visible part of em spectrum? Give its one use. In what way this component of light has harmful effects on humans?
✓

Answer

  1. $\gamma\text{ }\text{rays}.$

Produced in nuclear reactions and emitted by radioactive decay of nucleus.

Used in medicine to destroy cancer cells.

  1. Ultra violet rays

Used in LASIK eye surgery, UV lamps to kill germs in water purifier.

Causes sunburn/skin cancer/harms eyes when exposed to direct UV rays.

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