Question

Of the following types of electromagnetic radiation— radio waves, microwaves, gamma rays, and visible— which one has the longest wavelength? Which one has the highest frequency?

Short answer

Radio waves have the longest wavelength, and gamma rays have the highest frequency.

Step-by-step solution

Understanding Electromagnetic Spectrum

The electromagnetic spectrum is arranged according to the frequency or wavelength of electromagnetic radiation. A higher frequency means shorter wavelength and more energy, while a lower frequency means longer wavelength and less energy.

Ordering Types Based on Wavelength

From longest to shortest wavelength, the order of the mentioned types of electromagnetic radiation is: radio waves, microwaves, visible light, gamma rays.

Identifying Longest Wavelength and Highest Frequency

Therefore, radio waves have the longest wavelength, and gamma rays have the highest frequency, as the frequencies of electromagnetic waves are inversely proportional to their wavelengths.

Key concepts

Electromagnetic Radiation

Imagine sailing across a sea where waves of different lengths and heights pass by. This is akin to the variety we see in electromagnetic radiation, a form of energy that is all around us, though much of it is invisible to the human eye. The waves in this metaphor represent different types of electromagnetic radiation, including radio waves, microwaves, visible light, and gamma rays among others.

Electromagnetic radiation is a way that energy travels through space, and it can be characterized by its frequency or wavelength. Unique to electromagnetic waves is the fact that they do not require a medium to travel; they can move through the vast emptiness of space, which is why sunlight reaches the Earth. These waves also span a wide range of energies, which is determined by their frequency. High-energy waves, like gamma rays, can penetrate through materials and are used in medical applications to kill cancer cells. On the other hand, low-energy waves, like radio waves, are commonly used for communication.

Electromagnetic Wave Frequency

To comprehend the term electromagnetic wave frequency, think of it as how often the waves hit the shore in a given period. Frequency specifically refers to how many waves pass a fixed point in one second, measured in hertz (Hz).

The frequency of an electromagnetic wave directly ties into its energy and its place in the electromagnetic spectrum. The spectrum is like a grand piano, with low frequency waves on one end and high frequency waves on the other. Radio waves have low frequencies and therefore are like the deep notes of the piano. Conversely, gamma rays are like the high-pitched notes, possessing very high frequencies. Remember, frequency doesn't just influence the type of electromagnetic wave but also its properties. For example, our cell phones communicate using frequencies that are safe and won't cause much interference, while higher frequencies can carry more data or penetrate materials, which makes them valuable in medical diagnostics and treatments.

Wavelength of Electromagnetic Waves

Closely related to frequency is the concept of wavelength, which is the distance between two consecutive crests or troughs in a wave. You can think of it as the length of one complete wave cycle. In the context of the electromagnetic spectrum, wavelength provides another way to categorize electromagnetic radiation.

Different types of electromagnetic waves have their own distinctive wavelengths. For example, radio waves have very long wavelengths, measuring up to kilometers. On the other end, gamma rays have incredibly short wavelengths, less than the thickness of a human hair. This difference in wavelength affects how these waves interact with the world around us. Radio waves, with their longer wavelengths, can diffract around large objects and travel long distances, which is why you can hear a radio broadcast from far away. Conversely, the much shorter wavelengths of gamma rays allow them to interact with matter at a subatomic level, which is why they can be used in medical imaging to see inside the body.

Understanding the wavelength of electromagnetic waves is therefore critical for harnessing their specific properties in various technological applications.