Three voltmeters, all having different internal resistances are joined as shown in figure. When some potential difference is applied across A and B, their readings are $V_1$, $V_2$ and $V_3$. 
Choose the correct option.
To solve this problem, let's understand the configuration of the voltmeters in the circuit provided:
Now, let's verify why this option is correct and others are not:
Thus, the correct answer is: \(V_1 + V_2 = V_3\).
Tip: When dealing with voltmeters in series or parallel, always consider how they split or measure potential difference across points.
Applying Kirchhoff’s Voltage Law (KVL) across the loop: \(V_1 + V_2 - V_3 = 0 \implies V_1 + V_2 = V_3.\)
The Correct answer is: $V_1 + V_2 = V_3$
A black body is at a temperature of 2880 K. The energy of radiation emitted by this body with wavelength between 499 nm and 500 nm is U1, between 999 nm and 1000 nm is U2 and between 1499 nm and 1500 nm is U3. The Wien's constant, b = 2.88×106 nm-K. Then,

What will be the equilibrium constant of the given reaction carried out in a \(5 \,L\) vessel and having equilibrium amounts of \(A_2\) and \(A\) as \(0.5\) mole and \(2 \times 10^{-6}\) mole respectively?
The reaction : \(A_2 \rightleftharpoons 2A\)