MCQ Detailed View

The correct answer is Magnetic wave. MRI stands for Magnetic Resonance Imaging, a non-invasive medical imaging technique that uses strong magnetic fields and radio waves to create detailed images of the inside of the body.

Unlike X-rays or CT scans, which use ionizing radiation, MRI relies on the principle of nuclear magnetic resonance (NMR). The human body is largely composed of water molecules, and each water molecule contains hydrogen atoms. Hydrogen nuclei (protons) act like tiny magnets. When a person is placed in an MRI machine, a very strong magnetic field aligns these protons in the body.

Then, the machine applies radiofrequency (RF) pulses (a type of electromagnetic wave) to temporarily disturb this alignment. When the RF pulse is turned off, the protons return to their original alignment, releasing energy in the process. This released energy is detected by the machine and processed by a computer to generate highly detailed images of tissues and organs.

MRI is especially useful for imaging soft tissues like the brain, spinal cord, muscles, joints, and internal organs. It provides clearer contrast between normal and diseased tissues compared to X-rays or ultrasound. Because it does not use harmful ionizing radiation, MRI is considered safer for repeated scans.

It is important to note that while the main working principle of MRI depends on magnetic fields, radiofrequency electromagnetic waves also play a critical role in the imaging process. However, the foundation of the technique is the use of strong magnetic waves to manipulate proton alignment.

🔑 Key Facts:

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  MRI = Magnetic Resonance Imaging.

  
  


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  Uses strong magnetic fields + radiofrequency pulses.

  
  


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  Works on the principle of nuclear magnetic resonance.

  
  


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  Best for soft tissue imaging (brain, muscles, organs).

  
  


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  Safer than X-rays as it does not use ionizing radiation.

  
  

👉 Final Answer: In an MRI machine, the wave used is a Magnetic wave.