Question

In the circuit shown below, what will be the readings of the voltmeter ${V_3}$ ​and ammeter $A$ ?

$(A)800V,2A$
$(B)200V,2A$
$(C)220V,2.2A$
$(D)100V,2V$

Answer 1

A voltmeter is an instrument used for measuring the potential difference between two points in an electric circuit whereas an ammeter is a measuring device used to measure the electric current in a circuit.

Complete answer:
A voltmeter is always connected in series and never in a parallel combination. This is because
A voltmeter has high resistance and if it is connected in series then it would consume all the current. On the other hand an ammeter is always connected in series combination and never in a parallel combination. This is because an ammeter has a low resistance and if it is connected in parallel with the circuit, then all the current would flow through the ammeter and nothing would flow in the circuit.
This question is based on the LC circuit. An LC circuit, also called a resonant circuit, tank circuit, or tuned circuit, is an electric circuit consisting of an inductor and a capacitor connected together.
In this question, we can clearly see that,
${V_1} = {V_2}$
So, this a condition for resonance and we know that in resonance,
${V_3} = V$
${V_3} = 220V$
So, the reading of voltmeter ${V_3}$ is $220V$ .
Now, we need to measure current in order to get the reading of the ammeter $A$ .
So the ammeter reading, $I = \dfrac{V}{R}$
$I = \dfrac{{220}}{{100}}$
$I = 2.2A$
So, the reading in the ammeter is $2.2A$ .
So, the final answer is $(C)220V,2.2A$

Note:
There are various applications of LC circuits in our day to day lives which mainly include in radio, television, high-frequency heating, and generators, etc. This oscillator uses a tank circuit which includes a capacitor 'C' and an inductor 'L'.