Question

a galvanometer coil has a resistance of 12 ohm and the meter shows full scale deflection of a current of 3mA. how will you convert the meter into voltmeter of range 0 to 18 V​

Answer 1

Answer:

Converting galvanometer into voltmeter is done by adding resistance in series.

The resistance is given by R=

I

g

V

−G; G is resiatance of galvanometer.

⇒R=5988Ω

Explanation:

Hope it will help you.....

Answer 2

Question :

➀ A galvanometer coil has a resistance of 12 oh and the meter shows full scale deflection of a current of 3mA. how will you convert the meter into voltmeter of range 0 to 18V.

✿ Given :

➤ Resistance =12ohm

➤ Current=3mA

➤ Voltmeter of range 0 to 18V

Answer:

➡ Resistance of Galvanometer coil, G=12 ohm

• Current for which there is a full scale deflection, l=3mA =$\sf{3 \times 10^{-3}}$

•Range of the voltmeter is 0 which needs to be converted to 18 V

* V=18v

➡ Let a resistor of resistance R be connected in series with the galvanometer to convert it into a voltmeter . This resistance is given as :

$\\ \implies\large\sf{\dfrac{R}{I_{g} } -G}$

$\\ \implies\large\sf{ \dfrac{18}{3 \times 10^{-3} } -12 }$

$\\ \implies\large\sf{ 6000-12}$

$\\ \implies\boxed{\large\sf{ 5988 ohm }}$

➡ hence, resistor of resistance 5988 ohm is to be connected in series with the galvanometer.