Final answer:
The energy of a photon with a wavelength of 640 nm is calculated using the formula E = (h × c) / λ. After converting nm to meters and plugging in the values for Planck's constant and the speed of light, we find the energy to be approximately 3.1032 × 10-19 joules.
Step-by-step explanation:
To calculate the energy of a photon with a wavelength of 640 nm, we use the formula:
E = (h × c) / λ
Where:
- E is the energy of the photon
- h is Planck's constant (6.62607015 × 10-34 m2 kg / s)
- c is the speed of light in a vacuum (approximately 3 × 108 m/s)
- λ is the wavelength
First, convert the wavelength from nanometers to meters:
640 nm = 640 × 10-9 m
Then, plug in the values:
E = (6.62607015 × 10-34 m2 kg / s × 3 × 108 m/s) / (640 × 10-9 m)
E = 3.1032 × 10-19 J (joules)
The energy of a photon with a wavelength of 640 nm is approximately 3.1032 × 10-19 joules.