How many cells each marked (6V-12A) should be connected in mixed grouping so that it may be marked (24V-24 A)

Options

A. 4
B. 8
C. 12
D. 6

Answer

To solve the problem of how many cells marked (6V-12A) should be connected in mixed grouping to achieve a configuration marked (24V-24A), we can follow these steps:

### Step 1: Understand the Requirements
We need to achieve a total voltage of 24V and a total current of 24A using cells that each provide 6V and can handle 12A.

### Step 2: Determine the Number of Cells Needed in Series
To find out how many cells need to be connected in series to achieve the required voltage, we use the formula:

\[ \text{Number of cells in series} = \frac{\text{Total Voltage}}{\text{Voltage of one cell}} \]

Substituting the values we have:

\[ \text{Number of cells in series} = \frac{24V}{6V} = 4 \]

### Step 3: Determine the Number of Rows Needed in Parallel
Next, we need to determine how many rows of these series-connected cells we need to achieve the required current. The total current is given by:

\[ \text{Number of rows} = \frac{\text{Total Current}}{\text{Current of one cell}} \]

Substituting the values we have:

\[ \text{Number of rows} = \frac{24A}{12A} = 2 \]

### Step 4: Calculate the Total Number of Cells
Now, we can find the total number of cells required by multiplying the number of cells in series by the number of rows:

\[ \text{Total number of cells} = \text{Number of cells in series} \times \text{Number of rows} \]

Substituting the values we have:

\[ \text{Total number of cells} = 4 \times 2 = 8 \]

### Conclusion
Thus, the total number of cells needed is **8 cells**.

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