the frequency in hz of radiation having energy of 4.18 x 10^-21 j/photon?

E = hf.

Energy in J.
h = Planck's constant.
f = frequency in Hz

To find the frequency in Hz of radiation with a given energy, you can use the equation:

E = h * f

Where:
E is the energy of the radiation in joules (4.18 x 10^-21 J in this case),
h is Planck's constant (6.626 x 10^-34 J·s), and
f is the frequency of the radiation in Hz (the unknown).

To solve for f, rearrange the equation:

f = E / h

Now, substitute the given values:

f = (4.18 x 10^-21 J) / (6.626 x 10^-34 J·s)

Now multiply the numerator and denominator by 10^34 to simplify the calculation:

f = (4.18 x 10^-21 J) * (10^34 J·s / 6.626)

Calculate and evaluate the expression:

f ≈ 6.31 x 10^12 Hz

Therefore, the frequency of radiation with an energy of 4.18 x 10^-21 J/photon is approximately 6.31 x 10^12 Hz.