A galvanometer gives full scale deflection with `0.006 A` current. By connecting it to a `4990Omega` resistance, it can be converted into a voltmeter of range `30 V`. If connected to a `(2n)/249 Omega` resistance, it becomes an ammeter of range `0-1.5A`. the value of `n` is

Explanation

To solve the problem step by step, we will first analyze the information given and then apply the relevant formulas.

### Step 1: Understanding the Galvanometer
The galvanometer gives full-scale deflection with a current of \( I_g = 0.006 \, \text{A} \). It has an internal resistance \( R_g \) which we need to find.

### Step 2: Converting Galvanometer to Voltmeter
When connected to a \( 4990 \, \Omega \) resistance, it can measure up to \( 30 \, \text{V} \). The total resistance in the circuit when used as a voltmeter is:
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