A person connects four `1/4Omega` cells in series but one cell has its terminal reversed. The external resistance is `1 Omega.` If each cell has an emf of `1.5 V,` the currenet folowing is

Options

A. `4/3A`
B. `3/4A`
C. `1.5A`
D. zero

Explanation

To solve the problem step by step, we will follow these steps:

### Step 1: Understanding the Circuit
We have four cells, each with an EMF of \(1.5V\) and an internal resistance of \(\frac{1}{4} \Omega\). One of the cells has its terminal reversed. The external resistance in the circuit is \(1 \Omega\).

### Step 2: Calculate the Total EMF
In a series circuit, the total EMF is the sum of the individual EMFs. However, since one cell has its terminal reversed, we subtract the EMF of that cell from the total.

\[ \text{Total EMF} = E_1 + E_2 + E_3 - E_4 \]
Given that \(E_1 = E_2 = E_3 = E_4 = 1.5V\):

\[ \text{Total EMF} = 1.5 + 1.5 + 1.5 - 1.5 = 3V \]

### Step 3: Calculate the Total Internal Resistance
Since all four cells have an internal resistance of \(\frac{1}{4} \Omega\), the total internal resistance is the sum of the internal resistances of all four cells.

\[ \text{Total Internal Resistance} = r_1 + r_2 + r_3 + r_4 = \frac{1}{4} + \frac{1}{4} + \frac{1}{4} + \frac{1}{4} = 1 \Omega \]

### Step 4: Calculate the Total Resistance in the Circuit
The total resistance in the circuit is the sum of the total internal resistance and the external resistance.

\[ \text{Total Resistance} = \text{Total Internal Resistance} + \text{External Resistance} = 1 \Omega + 1 \Omega = 2 \Omega \]

### Step 5: Calculate the Current Using Ohm's Law
Using Ohm's Law, we can find the current flowing through the circuit. The formula for current is:

\[ I = \frac{V}{R} \]

Substituting the total EMF and total resistance:

\[ I = \frac{3V}{2 \Omega} = 1.5 A \]

### Conclusion
The current flowing in the circuit is \(1.5 A\).

---