Symmetry in Circuits

Q. The equivalent resistance between points A and B of an infinite network of resistance, each of $1\Omega$, connected as shown is

1. Infinite
2. Zero
3. $2\Omega$
4. $\frac{1+\sqrt{5}}{2}\Omega$

Q. The current flowing in the given circuit is $0.2A$. The potential difference between the points $A$ and $B$ will be

1. $0.4V$
2. $2V$
3. $0.2V$
4. $1V$

Q. A current of 3A flows in a circuit shown in the figure. The potential difference between A and B is

1. 4V
2. 3V
3. 2V
4. 1V

Q. A current of 2 A flows in a system of conductors as shown. The potential difference $(V_A-V_B)$ will be

1. + 1V
2. – 1 V
3. + 2V
4. – 2 V

Q.

Find the emf and internal resistance of a single battery which is equivalent to a combination of three batteries as shown in the figure.

1. $3V,5\Omega$

2. $7V,2\Omega$

3. $20V,5\Omega$

4. $3V,2\Omega$

Q. In an ac circuit the current and voltage are given by I is equal to 5 cos ω t and v is equal to 200 sint respectively power loss in the circuit is

Q. 53.: 36 cells each of internal resistance 0.5 ohm and e.m.f 1.5 V, each are used to send current through an external 2 ohm resistance. Find the value of maximum possible current and the number of rows and cells in row to obtain this value

Q. 82.Two conductors have the same resistance at 0 degree celsius but their temperature coefficients of resistance are A1 and A2. The respective temperature coefficients of their series and parallel combinations are nearly ?

Q. In the combination of resistances shown in the figure the potential difference between B and D is zero, when unknown resistance (x) is

1. $2\Omega$
2. The emf of the cell is required
3. $3\Omega$
4. $4\Omega$

Q. If the resistance of circuit having 12v source is increased by 4ohm, the current drops by 0.5A. What is the original resistance of the circuit?

Q. The plot of the variation of potential difference across a combination of three identical cells in series, versus current is shown below. What is the emf and internal resistance of each cell ?

Q. 1) Three capacitors of capacitances $2pF,3pF\text{and}4pF$ are connected in parallel.
A) What is the total capacitance of the combination?

2) Three capacitors of capacitances $2pF,3pF\text{and}4pF$ are connected in parallel.
B)Determine the charge on each capacitor if the combination is connected to a $100V$ supply?

Q. In the following circuit reading of voltmeter V is

1. 12 V
2. 8 V
3. 20 V
4. 16 V

Q.

What is the equivalent resistance between the points A and B of the circuit shown in figure.

1. $7\Omega$

2. $5\Omega$

3. $\frac{5}{7}\Omega$

4. $\frac{7}{5}\Omega$

Q. In the circuit below C, 20u C2 40 uF and = 50F. If no capacitor can sustain more than 50 V, then maximum potential difference between X and Y is

Q. Seven resistors each of resistance 5 ohm are connected as shown in figure. The equivalent resistance between points A and B is

1. 1 ohm
2. 7 ohm
3. 35 ohm
4. 49 ohm

Q. 121.Two copper wires have the same length but the second has diameter twice that of the first. If the resistance of the first is 2 ohms, the resistance of the second is 1) 1/2 ohm 2) 1 ohm 3) 4 ohm 4) 8 ohm

Q. In the given figure, equivalent resistance between A and B will be

1. $\frac{9}{14}\Omega$
2. $\frac{14}{3}\Omega$
3. $\frac{3}{14}\Omega$
4. $\frac{14}{9}\Omega$

Q. A frame of cube is made by wires each of resistance $r$, then the resistance across the body diagonal of the cube will be

1. $\frac{3r}{4}$
   
2. $\frac{5r}{6}$
   
3. $\frac{7r}{12}$
   
4. $\frac{6r}{5}$

Q. The equivalent resistance between the points $A$ and $B$ in the circuit shown in the following figure is

1. $10\Omega$
2. $20\Omega$
3. $30\Omega$
4. $40\Omega$

Q.

The resistance between the terminal points A and B of the given infinitely long circuit will be

1. $(\sqrt{3}-1)$
2. $(1+\sqrt{3})$
3. $(2+\sqrt{3})$
4. $(1-\sqrt{3})$

Q.

Find the equivalent capacitance of the infinite ladder shown in figure (31-E17) between the points. A and B.

Q.

Find the equivalent resistance of the circuits shown in figure (32-E17)between the points a and b. Each resistor has a resistance r.

Figure 32-E17

Q. All the bulbs below are identical. Which bulb(s) shine(s) most brightly ?

1. 1 only
2. 2 only
3. 3 and 4
4. 1 and 5

Q. The potential difference between points A and B, in a section of a circuit shown, is

1. 5 volt
2. 17 volt
3. 10 volt
4. 1 volt

Q. The equivalent resistance between points $A$ and $B$ in the network shown in figure is:

1. $\frac{15}{7}\text{R}$
2. $\frac{8}{7}\text{R}$
3. $\frac{12}{7}\text{R}$
4. $\frac{16}{7}\text{R}$

Q. The equivalent resistance between A and B in the circuit will be

1. $\frac{6}{5}r$
2. $\frac{5}{4}r$
3. $\frac{7}{6}r$
4. $\frac{8}{7}r$

Q. Find the equivalent capacitance of the combination between points $\text{P}$ and $\text{Q}$.

1. $5\mu \text{F}$
2. $12\mu \text{F}$
3. $10\mu \text{F}$
4. $16\mu \text{F}$

Q. A current of 4 A flows in a coil when connect to 12V d.c source .if the same coil is connected to a 12V , 50 rad/s a.c source , a current of 2.4 A flows in the circuit . determine the induc†an ce of the coil

Q. Seven resistors are connected as shown in the diagram.


The equivalent resistance in $\text{ohms}$ of this network between $A$ and $B$ is:

1. $8$
2. $6$
3. $12$
4. $20$