Questions: Which one of the following photons of electromagnetic radiation will have the greatest energy? One photon of red light (wavelength =650 nm) One photon of blue light (wavelength =470 nm) One photon of yellow light (wavelength =580 nm) One photon of green light (wavelength =550 nm) All of these will have the same energy.
Transcript text: Which one of the following photons of electromagnetic radiation will have the greatest energy?
One photon of red light (wavelength $=650 \mathrm{~nm}$ )
One photon of blue light (wavelength $=470 \mathrm{~nm}$ )
One photon of yellow light (wavelength $=580 \mathrm{~nm}$ )
One photon of green light (wavelength $=550 \mathrm{~nm}$ )
All of these will have the same energy.
Solution
Solution Steps
Step 1: Understanding the Relationship Between Wavelength and Energy
The energy of a photon is inversely proportional to its wavelength. This relationship is given by the equation:
\[
E = \frac{hc}{\lambda}
\]
where:
\(E\) is the energy of the photon,
\(h\) is Planck's constant (\(6.626 \times 10^{-34} \, \text{J}\cdot\text{s}\)),
\(c\) is the speed of light (\(3.00 \times 10^8 \, \text{m/s}\)),
\(\lambda\) is the wavelength of the photon.
Step 2: Comparing the Wavelengths
Given the wavelengths:
Red light: \(650 \, \text{nm}\)
Blue light: \(470 \, \text{nm}\)
Yellow light: \(580 \, \text{nm}\)
Green light: \(550 \, \text{nm}\)
Since energy is inversely proportional to wavelength, the photon with the shortest wavelength will have the greatest energy.
Step 3: Identifying the Shortest Wavelength
Among the given options, the blue light has the shortest wavelength of \(470 \, \text{nm}\).
Final Answer
The photon of blue light (wavelength \(=470 \, \text{nm}\)) will have the greatest energy.
\[
\boxed{\text{One photon of blue light (wavelength } = 470 \, \text{nm})}
\]