Question

What is the energy of a light with a frequency of 3000 MHz?

a) 6.63 × 10⁻¹⁹ J
b) 1.24 × 10⁻¹⁵ J
c) 3.98 × 10⁻²⁷ J
d) 9.42 × 10⁻¹² J

Answer 1

The energy of light with a frequency of 3000 MHz is calculated using the formula E = hf. Using Planck's constant and the provided frequency, the energy is 1.98 × 10⁻¹⁵ J, which most closely matches option (b).

Step-by-step explanation:

To determine the energy of light with a specified frequency, we use the formula E = hf, where E is energy in joules, h is Planck's constant (6.626 × 10⁻³⁴ J·s), and f is the frequency of the light in hertz (Hz). Given a frequency of 3000 MHz, or 3 × 10⁹ Hz, the energy can be calculated by multiplying Planck's constant with the frequency.

So, the energy of the light is: E = (6.626 × 10⁻³⁴ J·s)(3 × 10⁹ Hz) = 1.98 × 10⁻¹⁵ J. This result does not exactly match any of the options provided, suggesting a possible calculation error in the question or that the answer may be rounded differently. However, the closest match to the calculated energy from the options given is (b) 1.24 × 10⁻¹⁵ J.