A certain shade of blue has a frequency of 7.06 x 10" Hz. What is the energy of exactly one photon of this light? Planck's constant is h = 6.626 x 10 Js.

1 answer

To calculate the energy of one photon of light, we can use the formula:

\[ E = h \cdot f \]

where:

  • \( E \) is the energy of the photon (in joules),
  • \( h \) is Planck's constant (\(6.626 \times 10^{-34}\) J·s),
  • \( f \) is the frequency of the light (in hertz).

Combining these values, we have:

Given:

  • \( f = 7.06 \times 10^{14} , \text{Hz} \)
  • \( h = 6.626 \times 10^{-34} , \text{Js} \)

Now we can calculate \( E \):

\[ E = (6.626 \times 10^{-34} , \text{Js}) \cdot (7.06 \times 10^{14} , \text{Hz}) \]

Calculating \( E \):

\[ E = 6.626 \times 7.06 \times 10^{-34} \times 10^{14} \]

Calculating \( 6.626 \times 7.06 \):

\[ 6.626 \times 7.06 = 46.88456 \]

So:

\[ E = 46.88456 \times 10^{-20} , \text{J} \]

Now converting this to significant figures (3 significant figures from the frequency), we have:

\[ E \approx 4.69 \times 10^{-19} , \text{J} \]

Thus, the energy of exactly one photon of this light is approximately:

\[ \boxed{4.69 \times 10^{-19} , \text{J}} \]