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 `0.30 V`. If connected to a `(2n)/249 Omega` resistance, it becomes an ammeter of range `0-1.5A`. the value of `n` is

Answer

5

Explanation

For voltmeter we can write the following :
` 0.006 xx (4990 + R_(g)) = 30`
` 6 xx (4990 + R_(g)) = 30000`
` :. " " R_(g) = 10 Omega`

For ammeter we can write the following :
` 0.006 xx 10 = (1.5 - 0.006) xx (2n)/(249)`
` (2490)/(2n) = (1.500)/(0.006) - 1 = 249`
` 1- = 2 n`
` n = 5`