Question

PART-A: PHYSICS
In the ladder network shown, current through
the resistor 3 ohm is 0.25 A. The input voltage V
is equal to

(A) 10V
(B) 20 V

(C) 5V
(D) 15/2 V
-

​

Answer 1

Answer:

The voltage are 0.75 Volt

Step-by-step explanation:

Data:

The resistance = R = 3 ohm

The current = I = 0.25 A

Required:

Voltage = V = ?

Calculation:

We know that

Voltage = current × Resistance

That is

V = IR

Putting the values we get

V = (0.25)(3) = 0.75 Volt

So the voltage are 0.75 Volt

Answer 2

Answer:

V = 20V

Step-by-step explanation:

In order to understand the answer, first see the attached picture

Now first of all, we will be finding the total resistance of circuit.

Effective resistance in outmost limb is R’= 1+2+3= 6 ohm

1/R''  = 1/6 +1/6

R’’ = 3 ohm

R’’’ = 3 + 5 = 8 ohm

1/R''''  = 1/8 +1/8

R’’’’ = 4 ohm

Rnet = 7+4+9 = 20 ohm

Now ; V = I x Rnet

Let us find I;

Current through 1,2 and 3 ohm resistor = 0.25A

Current through 6 ohm resistor = 0.25A

Current through 5 ohm resistor = 0.25+0.25= 0.5A

Current through 8 ohm resistor = 0.5A

Current through total resistance = 0.5+0.5 = 1A

Hence I = 1 A;

V = IR;

V = 1 x 20;

V = 20V