Lifetimes of the molecules in the excited states are often measured by using pulsed radiation source of duration nearly in the nano second range of the radiation source has the duration of a 2ns and the Der of photons emitted during the pulse source is `2.5 xx 10^(15)`, calculate the energy of the source.

Explanation

To calculate the energy of the pulsed radiation source, we can follow these steps:

### Step 1: Understand the Given Data
We are given:
- Duration of the radiation source (t) = 2 ns = 2 × 10^(-9) seconds
- Number of photons emitted (n) = 2.5 × 10^(15)

### Step 2: Calculate the Frequency (ν)
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