
Given the following resistor network, the resistances are arranged as shown:
From the given circuit:
The resistances between points A, B, C, and D are:
\( 6 \, \Omega \) between A and C, \( 10 \, \Omega \) between B and C, \( 8 \, \Omega \) between C and D, \( 5 \, \Omega \) between B and D, and \( 4 \, \Omega \) between A and D.
First, combine the resistances in parallel and series:
Combine the \( 15 \, \Omega \) resistors in series between points A, C, and B. After the simplification, we get:
\( R_{\text{eq}} = 6 \, \Omega + 5 \, \Omega + 8 \, \Omega = 19 \, \Omega \)
Thus, the correct answer is:
\( R_{\text{eq}} = 19 \, \Omega \)

Thus the correct answer is 19 $\Omega$.
The equivalent resistance between the points \(A\) and \(B\) in the given circuit is \[ \frac{x}{5}\,\Omega. \] Find the value of \(x\). 
A Wheatstone bridge is initially at room temperature and all arms of the bridge have same value of resistances \[ (R_1=R_2=R_3=R_4). \] When \(R_3\) resistance is heated, its resistance value increases by \(10%\). The potential difference \((V_a-V_b)\) after \(R_3\) is heated is _______ V. 
The heat generated in 1 minute between points A and B in the given circuit, when a battery of 9 V with internal resistance of 1 \(\Omega\) is connected across these points is ______ J. 
The following diagram shows a Zener diode as a voltage regulator. The Zener diode is rated at \(V_z = 5\) V and the desired current in load is 5 mA. The unregulated voltage source can supply up to 25 V. Considering the Zener diode can withstand four times of the load current, the value of resistor \(R_s\) (shown in circuit) should be_______ \(\Omega\).
Two circular discs of radius \(10\) cm each are joined at their centres by a rod, as shown in the figure. The length of the rod is \(30\) cm and its mass is \(600\) g. The mass of each disc is also \(600\) g. If the applied torque between the two discs is \(43\times10^{-7}\) dyne·cm, then the angular acceleration of the system about the given axis \(AB\) is ________ rad s\(^{-2}\).

Method used for separation of mixture of products (B and C) obtained in the following reaction is: 