By what percentage will the illimination of the lamp decrease if the current drops by 20% ?
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AI Generated Solution
To solve the problem of how much the illumination of a lamp decreases when the current drops by 20%, we can follow these steps:
### Step 1: Understand the relationship between current and illumination
The illumination (or brightness) of a lamp is proportional to the power it dissipates. The power \( P \) dissipated by a lamp can be expressed using the formula:
\[ P = I^2 R \]
where \( I \) is the current flowing through the lamp and \( R \) is the resistance of the lamp.
### Step 2: Calculate the initial power
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