Difficulty: Easy
Correct Answer: Radio waves
Explanation:
Introduction / Context:
The electromagnetic spectrum covers a wide range of wave frequencies, from very low frequency radio waves to very high frequency gamma rays. Visible light occupies a narrow band in the middle of this spectrum. Understanding where visible light fits in, and which regions have higher or lower frequencies, is a basic part of physics and general science. This question focuses specifically on comparing the frequency of visible light with radio waves, X rays and ultraviolet radiation.
Given Data / Assumptions:
- Visible light lies between infrared and ultraviolet in the electromagnetic spectrum.
- Radio waves have the lowest frequencies among the options.
- X rays and ultraviolet rays are on the high frequency side compared to visible light.
- Higher frequency corresponds to higher photon energy.
Concept / Approach:
From lowest to highest frequency, the spectrum can be ordered approximately as radio waves, microwaves, infrared, visible light, ultraviolet, X rays and gamma rays. Visible light has higher frequency than all types of radio waves and microwaves, but lower frequency than ultraviolet and X rays. Therefore, among the given options, visible light has a higher frequency than radio waves but a lower frequency than ultraviolet rays and X rays. The only correct comparison in which visible light is higher is with radio waves.
Step-by-Step Solution:
Step 1: Recall the general order of the electromagnetic spectrum by frequency.
Step 2: Place radio waves at the low frequency end, below microwaves and infrared.
Step 3: Place visible light above infrared but below ultraviolet.
Step 4: Place ultraviolet above visible light, and X rays above ultraviolet.
Step 5: Compare visible light with each option. Visible light is higher in frequency than radio waves but lower than ultraviolet and X rays.
Step 6: Conclude that the only correct statement is that visible light has a higher frequency than radio waves.
Verification / Alternative check:
Visible light frequencies are roughly in the range of 4 * 10^14 to 7.5 * 10^14 hertz. Radio waves can have frequencies as low as a few kilohertz or megahertz, which are far lower than visible light. Ultraviolet radiation extends from about 7.5 * 10^14 hertz upward into the 10^15 hertz range, and X rays are still higher. These numerical ranges confirm that visible light sits between infrared and ultraviolet, above radio waves but below ultraviolet and X rays.
Why Other Options Are Wrong:
X rays: X rays have much higher frequencies and energies than visible light, so visible light does not exceed them in frequency.
Ultraviolet rays: Ultraviolet radiation is immediately above visible light in the spectrum, so it has higher frequency than visible light.
All of the above: This would claim that visible light has a higher frequency than radio, ultraviolet and X rays, which is not correct for the latter two.
Common Pitfalls:
Students sometimes remember only parts of the spectrum, such as that X rays are dangerous and ultraviolet causes sunburn, but forget the detailed ordering. Another confusion arises because visible light is the most familiar, leading some to think it must be in the middle of everything or higher than most other bands. Memorising the standard order from radio to gamma and practising comparisons helps avoid such mistakes.
Final Answer:
Visible light has a higher frequency than radio waves.
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