Find the energy stored in a 90cm length of a laser beam operating at 10mW.

Explanation

To find the energy stored in a 90 cm length of a laser beam operating at 10 mW, we can follow these steps:

### Step 1: Convert Power to Watts
The power of the laser beam is given as 10 mW. We need to convert this to watts:
\[ P = 10 \, \text{mW} = 10 \times 10^{-3} \, \text{W} = 0.01 \, \text{W} \]

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