Which of the following properties is not applicable to X-rays? They

Analyze the question: We need the property that does NOT apply to X-rays.

Concept: X-rays are high-energy electromagnetic waves, with very short wavelengths of about 10⁻¹⁰ m. Like all electromagnetic waves, they:

• travel in straight lines,
• travel at the speed of light (3 × 10⁸ m/s in a vacuum),
• affect photographic films (this is the basis of medical radiography),
• carry no charge.

Because X-rays carry no charge, electric and magnetic fields do not deflect them.

Checking each option:

• A. Travel in straight lines: True. X-rays are electromagnetic waves, so they travel in straight lines.
• B. Travel with the speed of light: True. All electromagnetic waves do.
• C. Are deflected by magnetic field: False. X-rays are uncharged photons, so a magnetic field exerts no force on them. This is the property that does not apply.
• D. Affect photographic films: True. X-rays blacken photographic film, which is how X-ray images are made.

**Answer: C.

Exam tip: Remember that charged particles (cathode rays, alpha and beta particles) are deflected by fields, while electromagnetic waves (radio waves, light, X-rays, gamma rays) are not. If you see "deflected by electric or magnetic field" in a question about X-rays or gamma rays, it is almost always the odd one out.