Chapte 11 Electromagnetic Waves

name me all the waves from the lowest wavelength to the highest?

Radio waves, microwaves, infrared, visible light, ultraviolet, X-rays, gamma rays.

Name me one characteristic of electromagnetic waves?

They travel at the speed of light in a vacuum.

What is the speed of electromagnetic waves in a vacuum?

About 3 × 10⁸ m/s (300,000,000 m/s).

Which electromagnetic wave has the highest energy?

Gamma rays have the highest energy among electromagnetic waves, possessing both very short wavelengths and high frequency.

What are microwaves commonly used for?

Microwaves are commonly used for cooking food, as well as in communication technologies such as radar and satellite transmissions.

True or False: All electromagnetic waves travel at the same speed in a vacuum.

True; they all travel at approximately 3 × 10⁸ m/s.

: What kind of wave are electromagnetic waves — transverse or longitudinal?
A: Transverse.

Electromagnetic waves are transverse waves, meaning their oscillations are perpendicular to the direction of wave propagation.

What is the unit for frequency?

The unit for frequency is hertz (Hz), which is defined as one cycle per second.

Which wave has a higher frequency: X-rays or radio waves?

X-rays have a higher frequency than radio waves, with X-rays being in the range of 10^16 to 10^19 Hz, while radio waves are typically between 3 kHz to 300 GHz.

What wave is mostly used in mobile phone communication?

Radio waves are mostly used in mobile phone communication due to their ability to carry information over long distances and penetrate various obstacles.

: What electromagnetic wave helps in detecting broken bones?

X-rays are the electromagnetic waves used primarily in medical imaging to detect broken bones, as they can penetrate soft tissue and create detailed images of hard structures like bones.

Which wave is used in cancer treatment?

Radiation therapy uses X-rays and other types of high-energy radiation to kill cancer cells and shrink tumors.

: Which part of the electromagnetic spectrum can humans see?

The visible spectrum includes wavelengths from approximately 380 to 750 nanometers, allowing humans to perceive colors like red, blue, and green.

Which electromagnetic wave is used in night vision and thermal imaging?

Infrared waves are utilized in night vision and thermal imaging technologies. They detect heat emitted by objects, allowing images to be formed even in low-light conditions.