Which of the following has least frequency ? IR radiations, visible radiation, radio waves.

Explanation

To determine which of the following has the least frequency among Infrared (IR) radiations, visible radiation, and radio waves, we need to examine the frequency ranges of each type of radiation.

### Step 1: Identify the frequency ranges of each type of radiation.
- **Infrared Radiation (IR)**: The frequency range is approximately \(10^{12}\) Hz to \(10^{14}\) Hz.
- **Visible Radiation**: The frequency range is approximately \(10^{14}\) Hz to \(10^{16}\) Hz.
- **Radio Waves**: The frequency range is approximately \(10^{6}\) Hz to \(10^{8}\) Hz.

### Step 2: Compare the frequency ranges.
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