which of the following forms of electromagnetic radiation has the highest energy? a. radio waves b. microwaves c. indigo visible light d. green visible light e. infrared radiation
The Correct Answer and Explanation is:
The correct answer is c. indigo visible light.
Electromagnetic radiation (EMR) consists of a range of wavelengths and frequencies, with different forms of EMR having varying amounts of energy. The energy of electromagnetic radiation is directly related to its frequency and inversely related to its wavelength, as given by the formula:
E=h⋅fE = h \cdot fE=h⋅f
Where:
- E is the energy,
- h is Planck’s constant (approximately 6.626×10−34 J\cdotps6.626 \times 10^{-34} \, \text{J·s}6.626×10−34J\cdotps),
- f is the frequency of the radiation.
In the electromagnetic spectrum, indigo visible light (with a wavelength of around 445–464 nm) has a higher frequency compared to green visible light, infrared radiation, microwaves, and radio waves. Since energy is proportional to frequency, indigo light has the highest energy among the options provided.
- Radio waves have the longest wavelengths and lowest frequencies, so they have the least energy.
- Microwaves have slightly higher frequencies and energy than radio waves, but still much lower than visible light.
- Infrared radiation has longer wavelengths than visible light but shorter than microwaves, thus it also has lower energy than indigo visible light.
- Green visible light falls in the middle of the visible spectrum, with wavelengths ranging from about 520 to 570 nm. It has lower energy than indigo light due to its longer wavelength.
Thus, indigo light stands out for having the highest frequency and consequently the highest energy among the given options.
